Simplify.

5^2/5^5

1/125

To simplify the expression 5^2/5^5, we can subtract the exponents since the base is the same:

5^(2-5) = 5^-3.

To further simplify this, we can rewrite 5^-3 as the reciprocal of 5^3:

5^-3 = 1/5^3.

Thus, 5^2/5^5 simplifies to 1/5^3.