If I understand correctly, what you're saying is 2^2n ÷ 2^5 = 2^4
the easiest way to do this is to get rid of the fraction by multiplying both sides by 2^5 and getting
2^2n = 2^9 (Because when you multiply exponents with the same base you add the exponents)
Because the bases are the same you can set the exponents equal to each other getting
2n=9
n=9/2 or 4.5