## Intermediate Algebra (12th Edition)

$r=\dfrac{I}{pt}$
Using the properties of equality, in terms of $r ,$ the given formula, $I=prt ,$ is equivalent to \begin{array}{l}\require{cancel} \dfrac{I}{pt}=\dfrac{prt}{pt} \\\\ \dfrac{I}{pt}=r \\\\ r=\dfrac{I}{pt} .\end{array}