Carcass wrote:
What is the smallest positive integer k such that the product \(1575 * k\) is a perfect square?
(A) 7
(8) 9
(C) 15
(D) 25
(E) 63
Kudos for the right answer and explanation
Let us Factorize 1575: \(1575 = 5 * 315 = 5 * 5 * 63 = 25 * 9 * 7 = 5^2 * 3^2 * 7\)
Since we need to make \(1575 * k\) to become a perfect square, we need to multiply 1575 with 7 so that the resulting number has even powers of all its primes (a perfect square has even exponents of all its
prime factors)
Thus, \(k = 7\)
\(Answer A\)