→ Rational number are those number which are expressible in form of p/q, where p and q are integers and q≠0.
→ If √15 is rational number then the value of n will be 4 because 4 is a perfect square it comes out of radical and becomes 3.
→ Now, 15 can be expressed as 2/1 which is in the form of p/q where p and q are integers and also q≠0.