In a parallel circuit the equivalent resistance is given by:
[tex]\frac{1}{R_{tot}}=\frac{1}{R_1}+\frac{1}{R_2}[/tex]
Plugging the resistances we have that:
[tex]\begin{gathered} \frac{1}{R_{tot}}=\frac{1}{10}+\frac{1}{5} \\ \frac{1}{R_{tot}}=\frac{5+10}{50} \\ \frac{1}{R_{tot}}=\frac{15}{50} \\ \frac{1}{R_{tot}}=\frac{3}{10} \\ R_{tot}=\frac{10}{3} \\ R_{tot}=3.33 \end{gathered}[/tex]
Therefore, the equivalent resistance is 3.33 Ω
