Quiz Chapter 10 –

Quiz Chapter 10 –

Problem 1:

According to the local union president, the mean gross income of plumbers in the Salt Lake City area follows a normal distribution with a mean of $48,000 and a population standard deviation of $2,000.  A recent investigative reporter for KYAK TV found, for a sample of 49 plumbers, the mean gross income was $47,600.  At the 0.05 significance level, is it reasonable to conclude that the mean income is not equal to $47,600?  Determine the p value.

1. State the Null and Alternate hypothesis:
2. State the test statistic:
3. State the Decision Rule:
4. Show the calculation:
5. What is the interpretation of the sample data?
6. Show the P value

Problem 2:

For a recent year, the mean fare to fly from Charlotte, North Carolina  to Chicago Illinois, on a discount ticket was $290.  A random sample of 12 round trip discount fares on this route last month shows:

At the 0.01 significance level, can we conclude that the mean fare has decreased?  What is the p value?

1. State the Null and Alternate hypothesis:
2. State the test statistic:
3. State the Decision Rule:
4. Show the calculation:
5. What is the interpretation of the sample data?
6. Show the P value