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

Answer 1

1-0.4+2=2.6,100*0.74=74,102*0.45=100*0.45+2*0.45=45+0.9=45.9,1.2*2.5+0.8*2.5=(1.2+0.8)*2.5=2*2.5=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=1.5+4 x=6,16+8x=40 8x=40-16 8x=32 x=4,(x-3)/2=7.5 (x-3)=2*7.5 (x-3)=15 x-3=15 x=3+15 x=18