六月jj 求解

alexuwang

5.一个连续数列一共有13个数，中数等于range,求最大数是多少 好像是18

6.一道PS（蛮难）:一个数是从2到29所有质数的乘积加1 

inclusive，问一下那个成立（1）这个数可以被2和29之间的一个质数整除

（2）这个数可以被29以后的一个质数整除 （3)记不清了厄          
    想了很久最后选2的 应该确定的哈

8.数列R和S,r和s分别是他们的标准差， 问r和s 那个大
    

vivi_1128

5. set the max=x and the min=y, so x=12+y, the range is x-y=12, and the model is =(x+y)/2.
so, we get (x+y)/2=12 and x-y=12 ==>2x=36 ==> x=18
6. (1) doesn't work. (2) works.
8. needs more information: what is R and S?

alexuwang

How to calc #6?

zhouray

以下是引用vivi_1128在2009-6-11 12:28:00的发言：
5. set the max=x and the min=y, so x=12+y, the range is x-y=12, and the model is =(x+y)/2.
so, we get (x+y)/2=12 and x-y=12 ==>2x=36 ==> x=18
6. (1) doesn't work. (2) works.
8. needs more information: what is R and S?

强！