简便计算7/8×5/13+7/13×3/8

问题描述:

简便计算7/8×5/13+7/13×3/8

7/8×5/13+7/13×3/8
=7/8×5/13+3/13×7/8
=7/8×(5/13+3/13)
=7/8×8/13
=7/13