645-58+42=用简便计算怎么算?

645-58+42=用简便计算怎么算?
2025-04-25 11:08:51
推荐回答(1个)
回答1:

645-58+42=用简便计算怎么算?
645-58+42
=645-(58-42)
=645-16
=629