7.02+3.9+1.98+2.1简便方法

2025-12-18 09:56:41
推荐回答(2个)
回答1:

7.02+3.9+1.98+2.1
=7.02+1.98+3.9+2.1
=(7.02+1.98)+(3.9+2.1)
=9+6
=15

回答2:

3.9+2.1+7.02+2.1