(11+13+12+15)/(2+9+8+10)=...

问题描述:

(11+13+12+15)/(2+9+8+10)=...

(11+13+12+15)/(2+9+8+10)
=51/29上 下求和(1)
=(29+22)/29
=(29/29)+22/29分配律
=1 又 22/29----------------(亦可由(1)式长除法得)