19 199+1999+19999 用简便运箅

4个十分之一和400个千分之一相等是对的还是错的?
2024-11-22 01:14:16
推荐回答(2个)
回答1:

=(辩喊20-1)+(200-1)+(2000-1)携罩野+(20000-1)
=(20000+2000+200+20)闷神-1×4
=22220-4
=22216

回答2:

19+199+1999+19999
=20-1+200-1+2000-1+20000-1
=22220-4
=22216