You may want to review fractional exponents first.
You can raise a number to a fractional exponent too. It's a good idea to do the problem in 2 steps. For example, suppose you have to compute 20482 / 11. You should first compute the 11th root of 2048, which is 2. Then you should square the 2, getting 4, the answer.
Of course, if the fraction has numerator 1, you won't need to do the second step. (And, if it has denominator 1, then it's not really a fraction at all!)
As always, the exponent could be 0, or a negative number. This means the same thing as always; so 125−1 / 3 = 1 / 1251 / 3 = 1 ⁄ 5.