(153+155+157+156+164)/157简便运算

问题描述:

(153+155+157+156+164)/157
简便运算

(153+155+157+156+164)/157
=[(153+161+3)+(155+156)+157]/157
=[(153+161)+(157+157)+157]/157
=157*5/157
=5
这种题都是有规律的

数学考试可以带计算机的

解:原式=157*5/157
=5
解题思路:括号里用简便方法,他们是等差数列,所以等于157*5

括号内5个数的和为,157-4+157-2+157+157-1+157+7=157*5
所以原式=5

高斯定律:连续几个数相加=(第一个数+第二个数)*项数/2
(153+155+157+156+164)/157
=[(153+161+3)+(155+156)+157]/157
=[(153+161)+(157+157)+157]/157
=157*5/157
=5

(153+155+157+156+164)/157
=[(153+161+3)+(155+156)+157]/157
=[(153+161)+(157+157)+157]/157
=157*5/157
=5

(153+155+157+156+164)/157
=(153+155+157+156+157+4+2+1)/157
=[(153+4)+(155+2)+157+(156+1)+157]/157
=(157+157+157+157+157)/157
=5*157/157
=5

(153+155+157+156+164)/157
=【(153+4)+(155+2)+157+(156+1)+(164-7)】/157
=(157+157+157+157+157)/157
=1+1+1+1+1
=5