Statistics

Directions: Test the following hypotheses using the Traditional Method.  You must show all the steps involved and the final statement must be phased appropriately for the problem.

1. From past records, a hospital found that 37% of all full-term babies born in the hospital weighed more than 7 pounds 2 ounces.  This year a sample of 100 babies showed that 23 weighed over 7 pounds 2 ounces.  At a level of significance of 2%, is there enough evidence to say the percentage has changed?


2. A recent study stated that the average single person household received at least 37 telephone calls per month.  To test the claim, a researcher surveyed 29 single person households and found that the average number of calls was 34.9.  The standard deviation of the sample was 6.  At a level of significance of 1%, can the claim be rejected?


3. The manager of a large factory believes that the average hourly wage of the employees is more than $9.78 per hour.  A sample of 18 employees has a mean hourly wage of $9.96.  The standard deviation of all salaries is $1.42.  At a level of significance of 5%, is there enough evidence to support the manager's claim?