Answer
reciprocal, $\displaystyle \quad... \frac{S}{R}=\frac{PS}{QR}$
Work Step by Step
Dividing with a rational expression $\displaystyle \frac{R}{S}$ is equivalent to multiplying with its reciprocal, $\displaystyle \frac{S}{R}.$
$\displaystyle \frac{P}{Q}\div\frac{R}{S}=\frac{P}{Q}\cdot\frac{S}{R}=\frac{PS}{QR}.$
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Fill the blanks with
reciprocal, $\displaystyle \quad... \frac{S}{R}=\frac{PS}{QR}$
