Question: For each situation, state the null and alternative hypothesis.

1. Researchers have postulated that, due to differences in diet, Japanese children have a lower mean blood cholesterol level than U.S. children. Suppose that the mean level of U.S. children is known to be 170.
2. A water quality control board reports that water is unsafe for drinking if the mean nitrate concentration exceeds 30 ppm. Water specimens are taken from a well.
3. Last year, your company’s service technicians took an average of 2.6 hours to respond to trouble calls from business customers who had purchased service contracts. Do this year’s data show a different average response time?
4. Census Bureau data show that the mean household income in the area served by a shopping mall is $42,500 per year. A market research firm questions shopper at the mall. The researchers suspect that mean household income of mall shoppers is higher than that of the general population.
5. The diameter of a spindle in a small motor is supposed to be 5 mm. If the spindle is either too small or too large, the motor will not work properly. The manufacturer measures the diameter in a sample of the motors to determine whether the mean diameter has moved away from the target.

Price: $2.99

Solution: The downloadable solution consists of 2 pages
Deliverable: Word Document