5/11+6/11+7/11+6/11*19 简便计算

问题描述:

5/11+6/11+7/11+6/11*19 简便计算

5/11+6/11+7/11+6/11*19
=(5/11+6/11)+7/11+6/11*(22-3)
=1+7/11-18/11+12
=(1+7/11-11/11-7/11)+12
=12