N positive integer problem with a + exponent

Here it is a problem that is driving me nuts...

Note: ^ means the exponent, in this case the exponent is "+".

If n is a positive integer, then n^+ denotes a number such that n < n^+ < n+1.

So decide which of the following options is greater (or if both ofthem are equal or if it is impossible to determine it).

Option A: 20^+ / 4^+

Option B: 5^+

What I did: 20^+ / 4^+ SO, (20/4)^+ , SO (5)^+ , so I concluded that both of them are equal, but the correct answer is " It canīt be determined which option is greater". Could anyone explain me why??