9.9乘以15怎么简便计算

2025-02-28 07:37:17
推荐回答(4个)
回答1:

9.9*15
=(10-0.1)*15
=10*15-0.1*15
=150-1.5
=148.5

回答2:

9.9×1.5
=(10-0.1)×1.5
=10× 1.5-1.5× 1
=15-1.5
=13.5

回答3:

9.9*15
=(10-0.1)*15
=150-1.5
=148.5

回答4:

9.9X15=10X15-0.1X15