Question

6.2x9.9（脱式）怎么简便计算？

6.2ⅹ9.9简便运算

Answer 1

脱式计算为
6.2*9.9
=6.2*（10-0.1）
=6.2*10-6.2*0.1
=62-0.62
=61.38

Answer 2

6.2*9.9=61.38

Answer 3

可采用乘法分配律，可得：6.2×（10-0.1）=6.2×10-6.2×0.1=62-0.62=61.38