Question

In: Statistics and Probability

A phone call to the service center has a normal distribution with mean 10 min and...

A phone call to the service center has a normal distribution with mean 10 min and standard deviation 2 min. During one day there were 5 phone calls and during the other day there were 6 calls. What is the probability that the sample average taken on each of the two days is at most 11?

Expert Solution

Solution :

Given that ,

mean = = 10

standard deviation = = 2

n = 6

= 10

= / n = 2 / 6

P( > 11) = 1 - P( < )

= 1 - P[( - ) / < (11 - 10) / 2 / 6 ]

= 1 - P(z < 1.22)

= 1 - 0.8888

= 0.1112

orchestra answered 2 years ago

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