45×12×35用简便方法计算?

2025-03-05 01:01:30
推荐回答(1个)
回答1:

(12+23+34)×(23+35+45)—(12+23+34+45)×(23+35)
=(12+23+34)×(23+35)+(12+23+34)×45—(12+23+34)×(23+35)-45×(23+35)
=(12+23+34)×(23+35)—(12+23+34)×(23+35)+(12+23+34)×45-45×(23+35)
=(12+23+34-23-35)×45
=11×45
=495