4X(2/15+1/6)-4/5怎样简便运算

问题描述:

4X(2/15+1/6)-4/5怎样简便运算

4X(2/15+1/6)-4/5
=4x(4/30+5/30)-24/30
=36/30-24/30
=6/30
=1/5