Question

If P(S) = 0.3, P(T ) = 0.4 and S and T are independent events, then P(S/T) is equal to

(a) 0.12 

(b) 0.2 

(c) 0.3 

(d) 0.4

Answer 1

Answer: (c) 0.3

S and T being independent events, 

P(S ∩ T) = P(S) × P(T) = 0.3 × 0.4 

P(S/T) = \(\frac{P(S\,\cap\,T)}{P(T)} = \frac{0.3\times 0.4}{0.4}\)  = 0.3