Question 190814
The probability that a trainee will remain with a company is 0.6. 
P(R) = 0.6
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The probability that an employee earns more than Rs.10, 000 per year is 0.5
P(10K) = 0.5
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The probability that an employee is a trainee who remained with the company or who earns more than Rs.10, 000 per year is 0.7
P(R or 10K) = 0.7
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What is the probability that an employee earns more than Rs.10, 000 per year given that he is a trainee who stayed with the company.
P(10K | R) = P(10K and R)/P(R)
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Note: P(10K and R) = P(R)+P(10K)-P(10K or R) = 0.6+0.5-0.7 = 0.4
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Therefore P(10K |R) = 0.4/0.6 = 2/3
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Cheers,
Stan H.