简便计算 (90+88分之1)×89分之1

问题描述:

简便计算 (90+88分之1)×89分之1

(90+1/88)×1/89
=(89+1+1/88)x1/89
=(89+89/88)x1/89
=89x1/89+89/88x1/89
=1+1/88
=1 又 1/88