A box holds 5 good and 3 faulty bulbs. Two bulbs are taken out one after the other without replacement. What is the probability that exactly one is faulty?

Explanation

1. 01

   Good then faulty: $\frac{5}{8} \times \frac{3}{7}$; faulty then good: $\frac{3}{8} \times \frac{5}{7}$.

2. 02

   $\frac{15}{56} + \frac{15}{56} = \frac{15}{28}$.