Answer
$R=9.00~\Omega$
Work Step by Step
Given
$\frac{1}{R}=\frac{1}{R_{1}}+\frac{1}{R_{2}}+\frac{1}{R_{3}}$
$R=?, R_{1}=30\Omega, R_{2}=18\Omega,R_{3}=45\Omega$
$\frac{1}{R}=\frac{1}{30}+\frac{1}{18}+\frac{1}{45}$
Therefore, $R=9.00\Omega$
How to use the calculator:
$30*x^{-1}+18*x^{-1}+45*x^{-1}=x^{-1}=$
