王晓丹家长:1-0.4+2=100×0.74=2、用简便方法计算102×0王晓丹家长:1-0.4+2=100×0.74=2、用简便方法计算102×0.451.2×2.5+0.8×2.53、笔算：（得数保留两位小数）1.7×0.45=19.4÷124、脱式计算.2.05×0.82+33.

Question

王晓丹家长:1-0.4+2= 100×0.74= 2、用简便方法计算102×0
王晓丹家长:1-0.4+2= 100×0.74= 2、用简便方法计算102×0.45 1.2×2.5+0.8×2.5 3、笔算：（得数保留两位小数）1.7×0.45= 19.4÷12 4、脱式计算.2.05×0.82+33.6 9.07-22.78÷3.4
5、解方程.x-1.5=4 16+8x=40 （x-3）÷2=7.5 【该条短信不支持回复】

Answer 1

1-0.4+2= 2.6
100×0.74= 74
102×0.45
=100x0.45+2x0.45
=45+0.9
=45.9
1.2×2.5+0.8×2.5
=（1.2+8）x2.5
=2x2.5
=5
1.7×0.45≈0.77
19.4÷12 ≈1.62
2.05×0.82+33.6
=1.681+33.6
=35.281
9.07-22.78÷3.4
=9.07-6.7
=2.37
x-1.5=4
x=4+1.5
x=5.5
16+8x=40
8x=40-16
x=24÷8
x=3
（x-3）÷2=7.5
（x/2）-1.5=7.5
x/2=7.5+1.5
x =9÷2
x =4.5
虽然都不难,但是题目挺多的,求个采纳,嘻嘻.