A coin is biased so that a head is twice as likely to occur as a tail. If the coin is tossed 3 times, then the probability of getting two tails and one head is-

Step-by-step solution

Given: P H = 2 P T We know that, P H + P T = 1 ⇒ 2 P T + P T = 1 ⇒ P T = 1 3 and P H = 2 3 ⇒ P 2 tails and 1 head = 1 3 × 1 3 × 2 3 × 3 ! 2 ! for arrangements ⇒ P 2 tails and 1 head = 2 9