Question

there are three coins. one is a two headed coin (having head on both faces) another is a biased coin that comes up tailss 25% of the time and third is an unbiased coin. one of the three coins is chosen at random and tossed it shows heads what is the probability that it was the two headed coin ?

Answer 1

Answer:

4/9

Step-by-step explanation:

Let us consider the 3 coins as A, B and C respectively.

Probability of getting head from coin A = 1

Probability of getting head from coin B= 25/100 = 1/4

Probability of getting head from coin C = 1/2

∴ probabilty of getting H by coin A is p(A/H)

using Bayes Theorem formula,

{1 * 1} / { (1 * 1) + (1 * 3/4) + (1 * 1/2) }

= 4/9