Question

A coin is weighted so that the probability of heads is 0.64. On average, how many coin flips will it take for the tails to first appear

Answer 1

1.563

Explanation:

Given :

Probability of head, p = 0.64

Number of flips it would take for tail to appear first :

Treatting the question as a geometric function :

Using the relation :

1 / p

Expected number of flips until first tail :

1 / P = 1/ 0.64 = 1.5625

E(x) = expected number of flips until first tail = 1.563