1100阧10减20阧……100简便法怎样写?

2025-02-22 23:49:17
推荐回答(1个)
回答1:

1100➖10 -20➖……100
=1100-(10+20+...+100)
=1100-(10+100)x10÷2
=1100-110x5
=1100-550
=550