Question

脱式计算，能简算的要简算．4.02×3.02+6.98×4.02 4.05÷0.81+2.4 ...

脱式计算，能简算的要简算．4.02×3.02+6.98×4.02 4.05÷0.81+2.4 0.389×4×0.25 2.43×99+2.43 8.4÷0.2÷0.5 64×4.5+3.6×45．

Answer 1

（1）4.02×3.02+6.98×4.02       
=4.02×（3.02+6.98）
=4.02×10
=40.2；

（2）4.05÷0.81+2.4
=5+2.4  
=7.4；

（3）0.389×4×0.25
=0.389×（4×0.25）
=0.389×1
=0.389；

（4）2.43×99+2.43
=2.43×（99+1）
=2.43×100
=243；

（5）8.4÷0.2÷0.5
=8.4÷（0.2×0.5）
=8.4÷0.1
=0.84；

（6）64×4.5+3.6×45
=6.4×45+3.6×45
=（6.4+3.6）×45
=10×45
=450．