# Question: The manager of a local fitness center wants an estimate

The manager of a local fitness center wants an estimate of the number of times members use the weight room per month. From a random sample of 25 members the average number of visits to the weight room over the course of a month was 12.5 visits with a standard deviation of 3.8 visits. Assuming that the monthly number of visits is normally distributed, determine a 95% confidence interval for the average monthly usage of all members of this fitness center.

## Answer to relevant Questions

Eight randomly selected batches of a chemical were tested for impurity concentration. The percentage impurity levels found in this sample were as follows: 3.2 4.3 2.1 2.8 3.2 3.6 4.0 3.8 a. Find the most efficient estimates ...Suppose that a survey of race fans at this week’s Daytona 500 NASCAR race were asked, Is this your first time attending the Daytona 500? From a random sample of 250 race fans, 100 answered in the affirmative. a. Find the ...What is the typical age of a person who renews his or her driver’s license online? From a random sample of 460 driver’s license renewal transactions, the mean age was 42.6 and the standard deviation was 5.4. Compute the ...Determine the margin of error for a 95% confidence interval for the difference between population means for each of the following (assume equal population variances): a. nx = 10 s2x = 6 x-bar = 200 ny = 16 s2y = 10 y-bar = ...A confidence interval for the difference between the means of two normally distributed populations based on the following dependent samples is desired: Before After 6 ............ 8 12 ................ 14 8 ...Post your question