Question

If 8 ships out of 10 ships arrive safely. Find the probability that at least one would arrive safely out of 5 ships selected at random.

Answer 1

Explanation:

P(safely reaches) = 1/3 P(not reaches safely) = 1 - 1/3 = 2/3

P(at least 4 arrive safely)

= P(4) + P(5) = 5C4 (1/3)4 (2/3) + 5C5 (1/3)5

= 11/35 = 11/243