Answer
$R_{1}=40.0\Omega$
Work Step by Step
Given
$\frac{1}{R}=\frac{1}{R_{1}}+\frac{1}{R_{2}}$
$R=15\Omega, R_{2}=24\Omega, R_{1}=?$
$\frac{1}{15}=\frac{1}{R_{1}}+\frac{1}{24}$
$\frac{1}{R_{1}}=\frac{1}{15}-\frac{1}{24}$
Therefore, $R_{1}=40.0\Omega$
How to use the calculator:
$15,*,x^{-1},-,24,*,x^{-1},=,x^{-1},=.$
