简便计算34215-345怎么做

分类: 作业答案 • 2022-04-12 11:37:50

问题描述：

简便计算342*15-34*5怎么做

答

342*15-34*5
=342*10+342*5-34*5
=3420+308*5
=3420+300*5+8*5
=3420+1500+40
=4960

答

342x15-34x5
=342x3x5-34x5
=(1026-34)x5
=992x5
=(1000-8)x5
=1000x5-8x5
=5000-40
4960

简便计算342*15-34*5怎么做