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P(RI-T) = 0.25, P(-R|T) = 0.2, P(T) = 0.1

What is P(R)?

O 0.245
O insufficient information
O 0.1060
O 0.305

User Omid
by
7.5k points

1 Answer

6 votes

Answer:

We can use Bayes' theorem to calculate P(R), which states that the probability of an event A given event B is equal to the probability of B given A multiplied by the probability of A, divided by the probability of B:

P(R|T) = P(T|R) * P(R) / P(T)

We can rearrange this equation to solve for P(R):

P(R) = P(R|T) * P(T) / P(T|R)

We are given that P(RI-T) = 0.25, which can be written as:

P(R∩T) = P(R|T) * P(T) = 0.25

We are also given that P(-R|T) = 0.2, which can be written as:

P(-R∩T) = P(-R|T) * P(T) = 0.2 * 0.1 = 0.02

We can use the law of total probability to find P(T|R):

P(T|R) = P(RI-T) / P(R) = 0.25 / P(R)

We can substitute these values into the equation for P(R) to get:

P(R) = P(R|T) * P(T) / P(T|R)

= 0.25 / [P(T|R) * P(T) + P(-R|T) * P(T)]

= 0.25 / [0.25 + 0.02]

= 0.1060

Therefore, the answer is option C: 0.1060.

User Zenel Rrushi
by
8.5k points