SOLUTION: 17. The population mean and standard deviation are given below. Find the required probability and determine whether the given sample mean would be considered unusual. For a sample

Algebra ->  Probability-and-statistics -> SOLUTION: 17. The population mean and standard deviation are given below. Find the required probability and determine whether the given sample mean would be considered unusual. For a sample      Log On


   

Question 872380: 17. The population mean and standard deviation are given below. Find the required probability and determine whether the given sample mean would be considered unusual.
For a sample of n = 75, find the probability of a sample mean being greater than 213 if μ = 212 and
σ = 6.1.
Found 2 solutions by stanbon, ewatrrr:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
For a sample of n = 75, find the probability of a sample mean being greater than 213 if μ = 212 and
σ = 6.1.
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z(213) = (213-212)/[6.1/sqrt(75)] = 1.4197
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Since the z-value is less than two 213 is not unusual.
Cheers,
Stan H.
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Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

 population: mean= 212, standard deviation = 6.1

Sample of 75

P(xbar > 213),   z = (213-212)/6.1/sqrt(75) = 1/.704 = 1.42

P(z > 1.42) = normalcdf(1.42,10)= .0778  0r 7.78%

TI syntax for P-value is normalcdf(smaller z, larger z) (Above: 10 a place-holder)