49999+4999+1999+499+49+5 怎样简算?382-98怎样简算?
来源:学生作业帮 编辑:神马作文网作业帮 分类:数学作业 时间:2024/11/16 03:55:38
49999+4999+1999+499+49+5 怎样简算?382-98怎样简算?
还有一个:(215+357+429+581+625)-205+347+419+571+615) 也是简算!
还有一个:(215+357+429+581+625)-205+347+419+571+615) 也是简算!
49999+4999+1999+499+49+5
= (49999+1)+(4999+1)+(1999+1)+(499+1)+(49+1)
= 50000 + 5000 + 2000 + 500 + 50
= 57550
382-98
= 382 - 100 + 2
= 282 + 2
= 284
(215+357+429+581+625)-(205+347+419+571+615)
= (215-205)+(357-347)+(429-419)+(581-571)+(625-615)
= 10 + 10 + 10 + 10 + 10
= 50
= (49999+1)+(4999+1)+(1999+1)+(499+1)+(49+1)
= 50000 + 5000 + 2000 + 500 + 50
= 57550
382-98
= 382 - 100 + 2
= 282 + 2
= 284
(215+357+429+581+625)-(205+347+419+571+615)
= (215-205)+(357-347)+(429-419)+(581-571)+(625-615)
= 10 + 10 + 10 + 10 + 10
= 50