Question

递等式计算，能简便的要简便:4/25×99+4/25

Answer 1

(4/25)×99+(4/25)
=(4/25)×(99+1)
=(4×25)×100
=4×4
=16.

Answer 2

4/25*100即100个4/25

Answer 3

（99+1）x4/25

Answer 4

（1）25×32×0.25
=25×4×2×4×0.25
=（25×4）×（4×0.25）×2
=100×1×2
=200；

（2）0.25×（0.4+40）
=0.25×0.4+40×0.25
=0.1+10
=10.1；

（3）0.67+1.28+9.33+0.72
=（0.67+9.33）+（1.28+0.72）
=10+2
=12；

（4）3.18-（0.33+1.18）
=3.18-0.33-1.18
=（3.18-1.18）-0.33
=2-0.33
=1.67；

（5）6.3÷35
=6.3÷（7×5）
=（6.3÷7）÷5
=0.9÷5
=0.18；

（6）[1-（0.5-0.25）]×0.6
=[1-0.25]×0.6
=0.75×0.6
=0.45；

（7）7.8×0.9+0.78
=0.78×9+0.78
=0.78×（9+1）
=0.78×10
=7.8；

（8）1.9-1.9×（1.9-1.9）
=1.9-1.9×0
=1.9-0
=1.9．