北师大版七年级数学上册同步练习:2.6 有理数的加减混合运算

适用年级:初一
试卷号:564335

试卷类型:课时练习
试卷考试时间:2018/8/17

1.单选题(共6题)

1.
式子-4-2-1+2的正确读法是(  )
A.减4减2减1加2B.负4减2减1加2
C.-4,-2,-1加2D.4,2,1,2的和
2.
王明同学记录了他所在的城市5月2日至5月6日每天最高气温的变化情况,且5月1日的最高气温为25 ℃,则气温最高的是(  )
时间
2日
3日
4日
5日
6日
每天最高气温的变化
(与前一天比较)
升2 ℃
降3 ℃
升6 ℃
降5 ℃
降4 ℃
 

 

A.5月2日B.5月3日C.5月4日D.5月6日
3.
将(+5)-(+2)-(-3)+(-9)写成省略加号和括号的和的形式,正确的是(  )
A.-5-2+3-9B.5-2-3-9
C.5-2+3-9D.(+5)(+2)(-3)(-9)
4.
下列运算结果错误的是(  )
A.(-20)+3-5-(-7)=-15B.9-10+(-2)-(-8)+3=8
C.D.(-8)-4+(-6)-(-1)=-17
5.
下列交换加数位置的变形中,正确的是(  )
A.1﹣4+5﹣4=1﹣4+4﹣5B.1﹣2+3﹣4=2﹣1+4﹣3
C.4﹣7﹣5+8=4﹣5+8﹣7D.﹣3+4﹣1﹣2=2+4﹣3﹣1
6.
小明今年在银行中办理了7笔储蓄业务:取出9.5元,存进5元,取出8元,存进12无,存进25元,取出12.5元,取出2元,这时银行现款增加了()
A.12.25元B.-12.25元C.10元D.-12元

2.选择题(共2题)

7.

根据短文理解,判断正误。

Be an Original

      It's said that we human beings are the only creatures who refuse to be what we are. One writer said, “When people are free to do what they want, they usually copy each other.” Yet nobody can be you as well as you can. Every successful person becomes successful because he or she discovered and developed his or her own special abilities. As a guy said, “One of the hardest things about climbing the ladder of success is getting through the crowd of copies at the bottom.”

      So remember you are a specialist. You're not made to be all things to all people. Surveys have shown that usually about 20 percent of all the people who know you don't really like you that much. You just can't please all the people all the time! So don't try to have peace at all costs, especially at the cost of your own success. “Don't stay where you're tolerated (忍受), go where you're celebrated!” Be yourself. Be an original (有独创性的人)! You really are one-of-a-kind. You're the first and last person who will ever be exactly like you.

      Do you know that over 90 percent of all flowers have no smell at all? It's the ones with a sweet fragrance (香味) and smell that we remember. So don't be afraid to be different, if it means being yourself. We are like rivers, “If we follow the easy path of least resistance, it will make us crooked (弯曲).” So don't follow where the path may lead, go where there is no path and leave your own trail. “You're born an original, don't die a copy!” Too many people are like the living dead, they've buried their real talents and abilities.

8.下列产品所用的塑料,具有热固性的是(   )

3.填空题(共2题)

9.
-15与+2.4的和减去+2.7的差是________.
10.
若规定图形表示运算a-b+c,图形表示运算x+z-y-w,则=________.

4.解答题(共6题)

11.
计算:(1)2+(-8)-(-7)-5; 
(2)(-40)-(-28)-(-19)+(-24).
12.
计算:
(1)|-3|+|-112|-|-10|;
(2)-0.21+(-5.34)-(+0.15)+|-10|;
(3)-|--(-)|+|(-)+(-)|.
13.
某牛奶厂在一条南北走向的大街上设有OABC四家特约经销店.A店位于O店的南面3千米处;B店位于O店的北面1千米处,C店在O店的北面2千米处.
(1)请以O为原点,向北的方向为正方向,1个单位长度表示1千米,画一条数轴,你能在数轴上分别表示出OABC的位置吗?
(2)牛奶厂的送货车从O店出发,要把一车牛奶分别送到ABC三家经销店,那么送货车走的最短路程是多少千米?
14.
如图,一只甲虫在55的方格(每一格边长为1)上沿着网格线运动,从A处出发去看望B、C、D处的甲虫,规定:向上向右为正,向下向左为负.例如:从A到B记为:(+1,+3);从C到D 记为:(+1,-2),其中第一个数表示左右方向,第二个数表示上下方向.
(1)填空:记为( ), 记为( );
(2)若甲虫的行走路线为:,请你计算甲虫走过的路程.
(3)若这只甲虫去Q的行走路线依次为:A→M(+2,+2),M→N(+2,-1),N→P(-2,+3),P→Q(-1,-2),请依次在图2标出点M、N、P、Q的位置.
15.
用简便方法计算:
(1)(-3)+(+8)-(-5);
(2)(-)+(+)+(+)+(-1);
(3)(-3)-(-)+(-0.5)+3
(4)(+3)+(-2)-(-5)-(+);
(5)(-0.25)+(-3)-|-1|-(-3);
(6)(+)+(+17)+(-1)-(+7)-(-2)+(-).
16.
问题:能否将1,2,3,4,…,10这10个数分成两组,使它们的差为5.
解:1+2+3+…+10=55,要使差为5,需将这10个数分成两组,一组的和为30,另一组的和为25,然后把它们相减.
下面给出一种分法,例如:(6+7+8+9)-(1+2+3+4+5+10)=5.
应用:在1,2,3,4,5,6,7,8,9,10这10个数前面任意添上“+”号或“-”号.
(1)能否使它们的和等于-7?若能,请给出一种分法;若不能,请说明理由.
(2)能否使它们的和等于-2?若能,请给出一种分法;若不能,请说明理由.
试卷分析
  • 【1】题量占比

    单选题:(6道)

    选择题:(2道)

    填空题:(2道)

    解答题:(6道)

  • 【2】:难度分析

    1星难题:0

    2星难题:0

    3星难题:0

    4星难题:0

    5星难题:0

    6星难题:10

    7星难题:0

    8星难题:1

    9星难题:3