S = {A, B, C}, P(B) = P(C), P(A) = 3P(C) P(B) =

Question

a. 0.1

b. 0.2

c. 0.3

d. 0.4

Answer 1

The sum of probabilities is always equal to 1 .

P(A) + P(B) +P(C) = 1 .

Let  P(B) = x  => P(C) = x 

P(A) = 3P(B) => 3x 

3x + x + x = 1

5x = 1 

x = 1/5 

x = 0.2 

P(B) = 0.2 

Hence option (b) is correct .