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【323556】2023七年级数学上册 第2章 有理数2.8有理数的加减混合运算课时练习 (新版)华东

时间:2025-01-15 19:23:01 作者: 字数:3615字
简介:


有理数的加减混合运算

(30分钟 50)

一、选择题(每小题4,12)

1.(杭州中考)计算(2-3)+(-1)的结果是 (  )

A.-2 B.0 C.1 D.2

2 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> .某地一天早晨的气温是-7,中午上升了11,午夜又下降了9,则午夜的气温是 (  )

A.5 B.-5 C.-3 D.-9

3.已知|a|=1,|b|=2,|c|=4,a>b>c,a-b+c= (  )

A.-1-3 B.7

C.-37 D.-1

 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> 二、填空题(每小题4,12)

4.已知有理数+3,-8,-10,+12,请你通过有理数的加减混合运算,使其运算结果最大,这个最大值是________.

5.七年级一班 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> 某次数学测验的平均成绩为80,数学老师以平均成绩为基准,记作0,把小龙、小聪、小梅、小莉、小刚这五位同学的成绩 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> 简记为+10,-13,0,+20,-2.问这五位同学的平均成绩是________.

6.一跳骚在一直线从0点开始,1次向右跳1个单位 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> ,紧接着第 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> 2次向左跳2 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> 个单位,3次向右跳3个单位,4次向左跳4个单位,…,依此规律跳下去,当它跳第100次落下时,落点处离0点的距离是________个单位.

三、解答题(26)

7.(10)计算:(1) <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> +(- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )+ <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> +(- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )+(- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> ).

(2) <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> 5.6+(-0.9)+4.4+(-8.1)+(-1).

(3)(-3 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )-(-1 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )-(-2 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )+(-1.75).

(4)-108-(-112)+23+18.

(5)(-4 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )-{3 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> -[-0.13-(-0. <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> 33)]}.

8.(6)若“三角” <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> 表示运算a-b+c,“方框 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> 表示运算x-y+z+w,写出 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> - <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> 表示的运算,并计算结果.

【拓展延伸】

9.(10)观察下面的变形规律:

 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> =1- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> ; <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> = <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> - <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> ; <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> = <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> - <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> ;…

解答下面的问题:

(1)n为正整数,请你猜想 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> =______.

(2)求和: <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> + <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> + <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> +…+ <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> .











答案解析

1.【解析】选A.(2-3)+(-1)=2-3-1=-2.

2.【解析】选B.根据题意可列式-7+11-9=-5,所以午 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> 夜的温度是零下5℃.

3.【解析】选A.由题意得a=±1,b=±2,c=±4,

又由a>b>c,可得a=±1,b=-2,c=-4.

所以当a=1,b=-2,c=-4,a-b+c=1-(-2)+(-4)=-1.

a=-1,b=-2,c=-4,a-b+c=(-1)-(-2)+(-4)=-3.

【变式训练】已知有理数a,b,c在数轴上的位置如图所示,|a|=1,|b|=2,|c|=4,a-b-c=________.

 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a>

【解析】a,c在原点的左侧,b在原点的右侧,所以b>0,c<0,a<0,因为|a|=1,

|b|=2,|c|=4,所以a=-1,b=2,c=-4,所以a-b-c=-1-2-(-4)=-1-2+4=1.

答案:1

4.【解析】(+3+12)-(-8-10)=15+18=33.

答案:33

5.【解析】五位同学的平均成绩:80+(10-13+0+20-2)÷5=80+3=83().

答案:83

6.【解析】向右跳记为正,向左跳记为负.

根据题意得第100次落下时,落点处离01-2+3-4+…+99-100=(1-2)+(3-4)+…+(99-100)=(-1)+(-1)+…+(-1)=-50,

即落点处在0点左侧50个单位处.

答案:50

7.【解析】(1) <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> 原式=[ <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> +(- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )]+[(- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )+(- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )]+ <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> =-1+ <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> =- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> .

(2)原式=(5.6+4.4)+(-0.9-8.1-1)

=10-10=0.

(3)原式=(-3 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> +1 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )+(2 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> -1 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )

=-2+1=-1.

(4)原式=-108+112+23+18=-108+153=45.

(5)原式=(-4 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )-(3 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> +0.13-0.33)=-7.7.

8.【解析】 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> - <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> =( <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> - <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> + <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )-[(-2)-3+(-6)+3]=

( <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> - <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> + <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )-(-2-3-6+3)=- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> -(-8)=- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> +8=7 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> .

9.【解析】(1) <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> - <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> .

(2)原式=1- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> + <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> - <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> + <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> - <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> +…+ <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> - <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> =1- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> = <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> .

【知识拓展】独特的埃及分数

  埃及同中国一样,也是世界上著名的文明古国.古代埃及人处理分数与众不同,他们一般只使用分子为1的分数.例如: <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> + <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> 表示 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> , <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> + <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> + <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> 来表示 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a>.现在有90个埃及分数: <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> , <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> , <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> , <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> ,…, <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> , <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> ,你能从中挑出10,加上正负号,使它们的和等于-1?

【解析】要从90个埃及分数中挑出10,加上正负号,使它们的 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> 和等于-1,这里就需要运用有理数的混合运算来解决问题.方法如下:

-1=-1+( <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> - <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )+( <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> - <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )+…+( <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> - <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )

=(-1+ <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )+(- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> + <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )+(- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> + <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )+…+

(- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> + <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )+(0- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )

=- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> +(- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )+(- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )+…+(- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> )+(- <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> ),

因此,要选的10个分数是:

 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> , <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> , <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> , <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> , <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> ,

 <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> , <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> , <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> , <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> , <a href="/tags/16/" title="课时" class="c1" target="_blank">课时</a> <a href="/tags/45/" title="混合" class="c1" target="_blank">混合</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/848/" title="华东" class="c1" target="_blank">华东</a> <a href="/tags/852/" title="有理数" class="c1" target="_blank">有理数</a> .

4