1/3*2/5+1/6*1/5+1/12*3/10

问题描述:

1/3*2/5+1/6*1/5+1/12*3/10

=2/15+1/30+1/40
=16/120+4/120+3/120
=23/120=2/15+1/30+1/40
=16/120+4/120+3/120
=23/120