The minimum number of times a fair coin needs to be tossed, so that the probability of getting at least two heads is at least 0.96, is

Step-by-step solution

P 2 + P 3 … ≥ 0.96 1 - P 0 + P 1 ≥ 0.96 1 - 0.96 ≥ n C 0 1 2 n + n C 1 1 2 n ⇒ 0.04 2 n ≥ 1 + n ⇒ 4.2 n ≥ n + 1 100 ⇒ 2 n + 2 ≥ n + 1 100 As, 2 10 ≥ 900 ⇒ n = 8