og11 Problem Solving 169题

kobemvp

If n is a positive integer and n^2 is divisible by 72, then the largest positive integer that must divide n is ?

A)6

B)12

C)24

D)36

E)48


这道题的题目怎么看不懂...根据答案来说 应该是能够整除N 的最小正整数才对啊....求指点...

kobemvp

谢谢楼上两位的解释..明白啦 原来是没有理解 A divides B 的意思~~~

reddragon

B？n是正整数，n方是72的倍数，问n是最大是几的整数的倍数。

zhongyaya

This is a tricky question which tests your reading comprehension.

If a and b are integers (with a not zero), we say a divides b if there is an integer c such that b = ac.

From the stimulus, we know that n MUST have a factor of 12. So 12 is the largest positive integer that MUST divide n. This means that for all possible values of n, 12 is the largest positive factor that each value of n MUST have.