In: Statistics and Probability
Assume that the population distribution of BMI among adults over 18 is Normal with mean μ = 38 and standard deviation σ = 12 and suppose the you have an SRS of 4 adults. What is the probability that your sample will have a mean BMI of 53 or greater? Use Table A: Standard Normal Table and round your answer to 4 decimal places.
Given that,
mean = μ = 38
standard deviation = 
 = 12
n = 4

 = μ = 38

 = 
 / 
 n = 12 / 
 4 = 6
P(
 > 53) = 1 - P(
 < 53)
= 1 - P[(
 - 
 
 ) / 
 
 < (53 - 38) / 6]
= 1 - P(z < 2.5)
Using z table,
= 1 - 0.9938
= 0.0062