SOLUTION: Please help, sort of confused. Suppose the average family of four washes an average of 2000 pounds of clothes a year. Assume the variable is normally distributed. Standard deviat

Algebra ->  Probability-and-statistics -> SOLUTION: Please help, sort of confused. Suppose the average family of four washes an average of 2000 pounds of clothes a year. Assume the variable is normally distributed. Standard deviat      Log On


   

Question 869875: Please help, sort of confused.
Suppose the average family of four washes an average of 2000 pounds of clothes a year. Assume the variable is normally distributed. Standard deviation of 187.5 pounds. A sample of 50 families is taken. Find two values so that there is a 99.9% chance that the mean falls between them.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

a = .001, a/2 = .0005  z = 3.29

ME = 3.29(187.5/sqrt(50) = 87.2

CI: 187.5- 87.2 > m < 187.50 + 87.2

 ( 100.3, 274.7)