12/7-(1/3*15/7+4/5)=?简便运算
问题描述:
12/7-(1/3*15/7+4/5)=?简便运算
答
12/7-(1/3*15/7+4/5)
=12/7-(5/7+4/5)
=12/7-5/7-4/5
=1-4/5
=1/5