Question

Two resistances, one 12 Ω and the other 18 Ω, are connected in parallel. What is the equivalent resistance of the parallel combination?

Answer 1

The equivalent resistance of the parallel combination

$$R=\frac{R_1R_2}{R_1+R_2}$$

$$R=\frac{12*18}{12+18}=7.2\:\Omega$$