4th root of 625
$$\sqrt[4]{625}=\sqrt[4]{25*25}=\sqrt[4]{5*5*5*5}=5$$
or
$$\sqrt[4]{625}=625^{1/4}$$
625^(1/4) = $${{\mathtt{625}}}^{\left({\frac{{\mathtt{1}}}{{\mathtt{4}}}}\right)} = {\mathtt{5}}$$