Question

Three identical resistors of 4 ohms are connected to give a combined resistance of 6 ohms. Which of the diagrams illustrates how this was done?

Answer 1

First two resistors will be in parallel. So,$\frac{1}{r}+\frac{1}{r}=\frac{2}{r}$

Now this resistor and the third resistor will be connected in series. So,

$\frac{r}{2}+r=\frac{3r}{2}$

Hence, the net resistance will be equal to $\frac{3r}{2}=6ohm$