有理数的加减法1、在列括号里填上适当的数(1)8-(-5)+(-4)-3=8+( )+( )+( )(2)(-1/2)+

1个回答

  • 1、在列括号里填上适当的数

    (1)8-(-5)+(-4)-3=8+(5)+(-4)+(-3)

    (2)(-1/2)+(-1/3)-(-1/4)-(-1/5)=

    (- 1/2)+(-1/3)+(1/4)+(1/5)

    2、计算

    (1)(+6)-(-3)+(-2)-(+6)

    =6+3-2-6

    =1

    (2)(+4.2)-(-5.8)-3

    =4.2+5.8-3

    =10-3

    =7

    (3)9-(-0.3)+(-6)-(-4.7)

    =9+0.3-6+4.7

    =15-6

    =9

    (4)(+1/3)-(+5/6)+(-1/6)-(-2/3)

    =1/3-5/6-1/6+2/3

    =1-2/3

    =1/3

    3、计算

    (1)-4.2+5.7-8.4+10

    =-4.2-8.4+5.7+10

    =-12.6+5.7+10

    =-6.9+10

    =3.1

    (2)6.1-3.7-4.9+1.8

    =6.1-(3.7+4.9-1.8)

    =6.1-6.8

    =-0.3

    (3)1/3-2/3+1

    =-1/3+1

    =2/3

    (4)-1/4+5/6+2/3-1/2

    =-1/4-2/4+6/5+6/4

    =-0.75+1.5

    =3/4(0.75)

    4、-3,+5与-7的和比它们的绝对值的和小多少?

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