Question

A fair coin is tossed a number of times till it tosses on a head. What is the probability that the coin tossing head on the 3rd toss.

Answer 1

Solution :

When we toss a fair coin, the probability of obtaining a head = 1/2 = 0.5

And probability of a tail = 1/2 = 0.5

If the head appears on third third toss then on the first and second toss it must have appeared tail.

Probability of obtaining tail on first toss = 0.5

Probability of obtaining tail on second toss = 0.5

Probability of obtaining head on third toss = 0.5

Hence, the probability that the coin tossing head on the 3rd toss is given by,

P = 0.5 × 0.5 × 0.5

P = 0.125

The probability that the coin tossing head on the 3rd toss is 0.125.