Question

the average age of doctors in a certain hospital is 50.0 years old. Suppose the distribution of ages is normal and has a standard deviation of 6.0 years. If nine doctors are chosen at random for a committee, find the probability that the average age of those doctors is less than 50.6. Assume that the variable is normally distributed

Answer 1

Solution :

Given that ,

mean = = 50.0

standard deviation = = 6.0

= / n = 6.0 / 9 = 2

P( < 50.6) = P(( - ) / < (50.6 - 50.0) / 2)

= P(z < 0.3)

= 0.6179

Probability = 0.6179