2.5×3.6和1.3÷2.5的简便运算分别是什么?

2.5×3.6
=2.5×4×0.9
=10×0.9
=9

1.3÷2.5
=(1.3×4)÷(2.5×4)
=5.2÷10
=0.52

解：2.5×3.6
＝2.5×4×0.9
=10×0.9
=9

1.3÷2.5
=（1.3×4）÷（2.5×4）
=5.2÷10
=0.52

2.5X4X0.9=9
1.3X4÷(2.5X4)=0.52

2.5*3.6
2.5*(4-0.4)=2.5*4-2.5*0.4=10-1=9
1.3/2.5
1.3/(5/2)
=2.6/5
=(2.5+0.1)/5
=2.5/5+0.1/5
=0.5+0.02
=0.52
抱歉，找不到乘法和除法就用“*”和“/”代替了，希望不要有意见，哈哈

很好

2.5×3.6
=2.5×(4-0.4)
=2.5×4-2.5×0.4
=10-1
=9
1.3÷2.5
=(1.3×4)÷(2.5×4)
=5.2÷10
=0.52