Answer:
1/625
Explanation:
The dots between the fractions mean multiply. Multiply all the numerators together, then all the denominators.
1x1x1x1 = 1
5×5×5×5 = 625
If you put it in a calculator, you get 0.0016
or as an exponential expression
or
Negative exponents mean "the reciprocal of the base to the power"
in this case, 5^4 is
and that's 625. the reciprocal is 1/625.