Explanation:

- When rolling a pair of dice, the probability of getting a doublet (both dice showing the same number) is 1/6. This is because there are 6 possible doublets (1-1, 2-2, 3-3, 4-4, 5-5, 6-6) among the 36 possible rolls.

- Rolling the dice three times gives three Bernoulli trials, each with a success probability of 1/6.

- We want the probability of exactly two successes (doublets) in three rolls.

- Use the binomial probability formula: \(P(X = k) = \binom{n}{k} p^k (1-p)^{n-k}\), where \(n = 3\), \(k = 2\), \(p = 1/6\).

- Calculating this gives: \(\binom{3}{2} \left( \frac{1}{6} \right)^2 \left( \frac{5}{6} \right) = 3 \times \frac{1}{36} \times \frac{5}{6} = \frac{15}{216} = \frac{5}{72}\).

Option 3: 5/72 is the correct choice.