Question:
1. A simple random sample of 50 speeds (in mph) is obtained from cars on a section of I-95 through Ft. Lauderdale, FL. The Sample has a mean of 67.3 mph and a standard deviation of 7.4 mph. Use a 0.05 significance level to test the claim that the mean speed of all cars is greater than the posted speed limit of 65 mph.
2. A simple random sample of 50 speeds (in mph) is obtained from cars on a section of I-95 through Ft. Lauderdale, FL. The Sample has a mean of 67.3 mph and a standard deviation of 7.4 mph. Use a 0.05 significance level to test the claim that the mean speed of all cars is greater than the posted speed limit of 65 mph. Assuming that a statistical software analysis routine such as stat-crunch computed a p-value of 0.01635. What would be the true statement?
3. When planning for construction of a parkway, engineers must consider the weights of cars to be sure that the road surface is strong enough. A simple random sample of 35 cars yields a mean of 3,500 lb. and a standard deviation of 525 lb. Use a 0.01 significance level to test the claim that the mean weight of all cars is less than 3,700 lb. show all 8 steps.
- State in symbolic form the claim:
- State in Symbolic form the opposite of the claim:
- State in symbolic form the null and alternate hypotheses:
- State the significance level or (a)
- Verify that the technical conditions are satisfied.
- Based upon the statcrunch analysis, what is the p-value for your hypothesis test?
- What is your conclusion about the null hypothesis? Fully justify your conclusion by referring to the P-value and the significance level.
- What is your conclusion about the claim made in the statement of the problem?
- 4.This Question requires the use of "Data Set 1 Body Measurement (Males) available in StatCrunch.
- At the 0.05 significan level, test the claim that the average weight of all men is less than or equal to 77kg: State all 8 steps.
5. In a recent Gallup Poll of 511 adults, 327 said that they were in favor of the death penalty for a person convicted of murder. We want to use a 0.01 significance level to test the claim that more than 50% of adults are in favor of the death penalty for a person convicted of murder. Show all 8 steps.
6. In on study of 71 smokers who tried to quit smoking with nicotine patch therapy, 39 were smoking one year after the treatment and 32 were not smoking one year after the treatment. Use 0.05 significance level to test the claim that among smokers who try to quit the nicotine patch therapy, more than 50% are smoking one year after the treatment. Show all 8 steps.