7.9/0.25简便运算

问题描述:

7.9/0.25简便运算

7.9÷0.25
=(8-0.1)÷1/4
=(8-0.1)×4(×分数的倒数)
=8×4-0.1×4
=32-0.4
=31.6

上下乘以4,就是7.9*4,再简就是(8-0.1)*4=32-0.4=31.6

7.9÷0.25
=7.9×4÷(0.25×4)
=7.9×4÷1
=(8-0.1)×4
=8×4-0.1×4
=32-0.4
=31.6