8分之3*7分之1+8分之3*7分之5

问题描述:

8分之3*7分之1+8分之3*7分之5

3/8 * 1/7 + 3/8 * 5/7
= 3/8 * (1/7 + 5/7)
= 3/8 * 6/7
= 3/4 * 3/7
= 9/28