## College Algebra (11th Edition)

$25$
$\bf{\text{Solution Outline:}}$ Use the laws of exponents and the definition of rational exponents to simplify the given expression, $\dfrac{125^{7/3}}{125^{5/3}} .$ $\bf{\text{Solution Details:}}$ Using the Quotient Rule of the laws of exponents which states that $\dfrac{x^m}{x^n}=x^{m-n},$ the expression above simplifies to \begin{array}{l}\require{cancel} 125^{\frac{7}{3}-\frac{5}{3}} \\\\ 125^{\frac{2}{3}} .\end{array} Using the definition of rational exponents which is given by $a^{\frac{m}{n}}=\sqrt[n]{a^m}=\left(\sqrt[n]{a}\right)^m,$ the expression above is equivalent to \begin{array}{l}\require{cancel} (\sqrt[3]{125})^2 \\\\= (\sqrt[3]{5^3})^2 \\\\= (5)^2 \\\\= 25 .\end{array}