Three resistors of resistance $R = 2$ ohm each are connected in parallel. Find the total resistance of the combination.
In a parallel connection the reciprocal resistances add up:
$$\frac{1}{R} = \frac{1}{R_1} + \frac{1}{R_2} + \frac{1}{R_3} = \frac{1}{2} + \frac{1}{2} + \frac{1}{2} = \frac{3}{2}$$
$$R = \frac{2}{3} \approx 0.67 \text{ ohm}$$
$R = 2/3 \approx 0.67$ ohm