2.5*3.6和1.3/2.5用简便方法计算
问题描述：
2.5*3.6和1.3/2.5用简便方法计算
答
2.5x3.6
=2.5x4x0.9
=10x0.9
=9
1.3÷2.5
=(1.3x4)÷(2.5x4)
=5.2÷10
=0.52