(2/15+5/12+2/3)×60简便

(2/15+5/12+2/3)×60
简便

=2/15X60+5/12X60+2/3X60
=8+25+40
=73

将60代入每个数相乘...
这个最简便...

(2/15+5/12+2/3)×60
(8/60+25/60+40/60)*60
8+25+40
73