Question

A fair coin is flipped multiple times until it lands on heads. If the probability of landing on heads is 50%. What is the probability of first landing on heads on the third attempt?

Answer 1

1/8

Explanation:

Given that A fair coin is flipped multiple times until it lands on heads.

The coin is unbiased.

We have to find the probability of first landing on heads on the third attempt.

We know that in a unbiased coin, each toss is independent of the other and also P(H) = P(T) = 0.5 in each attempt.

REquired probability = Probability of first landing on heads on the third attempt

= Prob of (I two trials result in tail and third result in head)

=P(I tail) P(II tail) P(III head) (since each trial is independent)

=
`((1)/(2) )((1)/(2) )((1)/(2) )=(1)/(8)`