SOLUTION: After going to a fast food restaurant, customers are asked to take a survey. Out of a random sample of 340 customers, 290 said their experience was “satisfactory.” Let p represent

Algebra ->  Probability-and-statistics -> SOLUTION: After going to a fast food restaurant, customers are asked to take a survey. Out of a random sample of 340 customers, 290 said their experience was “satisfactory.” Let p represent       Log On


   



Question 1120543: After going to a fast food restaurant, customers are asked to take a survey. Out of a random sample of 340 customers, 290 said their experience was “satisfactory.” Let p represent the proportion of all customers who would say their experience was “satisfactory.”
A) What is the point estimate for p?
B) Construct a 99% confidence interval for p.
C) Give brief interpretation of this interval.

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
Point estimate is the results 290/340 or 0.8529
99% CI ls mean +/- z0.995* sqrt (p*(1-p)/n)
The interval is 2.576*sqrt(0.8529*0.1471/340); sqrt term is 0.0192
The CI is 0.8529-0.0495, 0.8529+0.0495 or (0.8034, 0.9024)
We don't know the true proportion of customers, but we are extremely confident it lies in the above interval.