7.2*1.02 简便计算
问题描述:
7.2*1.02 简便计算
68*0.99 都要简便计算
答
1.
7.2*(1+0.02)
=7.2+(7+0.2)*0.02
=7.2+0.14+0.004
=7.344
2.
68*(1-0.01)
=68-0.68
=67.32