简便运算:8分之7加8分之1*5分之4=多少?
问题描述:
简便运算:8分之7加8分之1*5分之4=多少?
答
7/8+1/8*4/5
=7*1/8+1/8*4/5
=1/8*(7+4/5)
=1/8*(8-1/5)
=1-1/40
=39/40