Question

9

R and T are two mutually exclusive events.
P(R) = 0.2 and P(R or 1) = 0.69
Work out P(not T).

Answer 1

P(not T ) = 0.51

Explanation:

Step(i):-

Given that the R and T are two mutually exclusive events

P(R∩T) = 0

Addition theorem on probability

P(RUT) =P(R)+P(T) - P(R∩T)

P(RUT) =P(R)+P(T) - 0

P(RUT) =P(R)+P(T)

Step(ii):-

Given P(R) = 0.2 and P(RUT) = 0.69

P(RUT) =P(R)+P(T)

P(T) = P(RUT) -P(R) = 0.69 -0.2

P(T) = 0.49

P(not T) = 1- P(T)

P(not T ) = 1 - 0.49 = 0.51

Final answer:-

P(not T ) = 0.51