用简便方法计算7.2÷0.9+2.1 27.3÷1.2-8.8 9.6-2.4×3.5

问题描述:

用简便方法计算7.2÷0.9+2.1 27.3÷1.2-8.8 9.6-2.4×3.5

7.2÷0.9+2.1
=8+2.1
=10.1
27.3÷1.2-8.8
=27.3÷0.3÷4-8.8
=22.75-8.8
=13.95
9.6-2.4×3.5
=2.4×4-2.4×3.5
=2.4×(4-3.5)
=2.4×0.5
=2.4÷2
=1.2第一个怎么不用简便运算?7.2÷0.9+2.1 =(7.2×10)÷(0.9×10)+2.1=72÷9+2.1=8+2.1=10.1