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.
- State the Null and Alternate hypothesis:
- State the test statistic:
- State the Decision Rule:
- Show the calculation:
- What is the interpretation of the sample data?
- 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:
286 | 290 | 285 | 291 | 287 | 275 | 262 | 289 | 274 | 276 | 297 | 262 |
At the 0.01 significance level, can we conclude that the mean fare has decreased? What is the p value?
- State the Null and Alternate hypothesis:
- State the test statistic:
- State the Decision Rule:
- Show the calculation:
- What is the interpretation of the sample data?
- Show the P value