(5/6-3/9)*(0.25+5/7)

问题描述:

(5/6-3/9)*(0.25+5/7)

27/56

(5/6-3/9)*(0.25+5/7)
(15/18-6/18)*(7/28+20/28)
=1/2*27/28
=27/56