Question

1.（2/18-3/18-1/18）X36 2.（1/4-1/2-1/8）X128 3.[9X(-4)]X(-1/4) 4. 2.25x(-2.3)X3/25

5.(-2.1)X6.5X(-3/7) 写出过程能简便就简便！过程不能！！一步一步！

Answer 1

1.（2/18-3/18-1/18）X36
=2/18*36-3/18*36-1/18*36
=4-6-2
=-4
2.（1/4-1/2-1/8）X128
=1/4*128-1/2*128-1/8*128
=32-64-16
=-48
3.[9X(-4)]X(-1/4)
=9*(-4)*(-1/4)
=9*1
=9
4. 2.25x(-2.3)X3/25
=2.25*3/25*(-2.3)
=-621/1000

5.(-2.1)X6.5X(-3/7)
=(-2.1)*(-3/7)*6.5
=0.9*6.5
=5.85

追问

2.25*3/25 这个等于多少！

追答

4. 2.25x(-2.3)X3/25
=2.25*3/25*(-2.3)
=27/100*(-2.3)

=-621/1000

Answer 2

1.（2/18-3/18-1/18）X36
=-2/18x36
=-4

2.（1/4-1/2-1/8）X128
=1/4x128-1/2x128-1/8x128
=32-64-16
=-48

3.[9X(-4)]X(-1/4)
=36x1/4
=9

4. 2.25x(-2.3)X3/25
=-9/4x3/25x23/10
=-27/100x23/10
==621/1000

5.(-2.1)X6.5X(-3/7)
=21/10x3/7x13/5
=9/10x13/5
=117/50

追问

（2/18-3/18-1/18）这个是怎么算的？2-3好像-不了啊！？怎么算的！

追答

2/18-3/18-1/18= -2/18 呀

追问

那第四题的,-9/4 23/10 从哪里来的？？

追答

2.25=9/4
2.3=23/10

追问

2.25=9/4！这个怎么变的？

追答

2.25=225/100=9/4