If n is a positive integer and n^2 is divisible by 72, then the largest positive integer that must divide n is Options:  A) 6  B) 12  C) 24  D) 36  E) 48
possible values of n = 12, 24, 36 and 48.   But it is 12 that can divide all the possible values of n. If we consider 48, it will not divide 12, 24 and 36.   Hence, 12 is the value that MUST divide n.   ANSWER:12
<result>B</result>
If n is a positive integer and n^2 is divisible by 72, then the largest positive integer that must divide n is