SOLUTION: A normal population has a mean of 66 and a standard deviation of 4. You select a sample of 48. Compute the probability the sample mean is: (Round z values to 2 decimal place

Algebra ->  Probability-and-statistics -> SOLUTION: A normal population has a mean of 66 and a standard deviation of 4. You select a sample of 48. Compute the probability the sample mean is: (Round z values to 2 decimal place      Log On


   

Question 931785: A normal population has a mean of 66 and a standard deviation of 4. You select a sample of 48.

Compute the probability the sample mean is: (Round z values to 2 decimal places and final answers to 4 decimal places.)

(a) Less than 65.
Probability
(b) Between 65 and 67.
Probability
(c) Between 67 and 68.
Probability
(d) Greater than 68.

Probability

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
mean of 66 and a standard deviation of 4.
n = 48, z+=blue+%28x+-+68%29%2Fblue%284%2Fsqrt%2848%29%29+=blue+%28x+-+68%29%2Fblue%28.58%29+
P(x < 65) = P(z <-1/.58) = normalcdf(-100, -1.72)
P(65 < x <67) = P(-1.72 < z < 1.72) = normalcdf(-1.72, 1.72)
P( 67< x < 68) = P(1.72 < z < 3.45)=normalcdf(1.72, 3.45)
P(x > 68) = P(z > 3.45) = normalcdf(3.45, 100)