If n and y are positive integers and 450y = n^3, which of the following must be an integer? I. y/(3x2^2x5), II. y/(3^2x2x5), III. y/(3x2x5^2)
rnaah wrote:If n and y are positive integers and 450y = n^3, which of the following must be an integer? I. y/(3x2^2x5), II. y/(3^2x2x5), III. y/(3x2x5^2)
450y = n^3
450 = 2 * 3² * 5², so 2 * 3² * 5² * y = n^3
For the above equation to be true, y = 2² * 3 * 5 (since the right hand side is the power of 3)
So, I is true.
