A test is being designed to compare the wearing quality of two brands of automobile tires. The automobiles will be selected and equipped with the new tires and then driven under "normal" conditions for one month. Then a measurement will be taken to determine how much wear took place. If a sample of cars will be selected randomly, equipped with one tire of brand A, and one tire of brand B (the other two tires are not part of the test), and driven for a month.

. A test is conducted to compare the tread wear of certain type of tires on highways paved with asphalt and highways paved with concrete. Road tests were conducted with the same type of tires on two types of highways. Summary data on the mileage of the tires up to a certain level of wear are given below. Sample Size Sample Mean Sample Standard Dev. Asphalt 35 29,700 9,700 Concrete 35 25,500 7,800 Does this information suggest that tires wear faster on concrete-paved highways than asphalt paved highways? Test using  = 0.01. Use the 5 step method.

To study the effect of temperature on the tendency for vehicle tires to puncture, 1000 drivers in a large city were recruited and provided with two types of tires for their vehicles. For the three winter months during the year-long study, the drivers used Brand A winter tires on their vehicles. For the other nine months, the drivers used Brand B all-season tires on their vehicles. At the end of the year, the proportion of Brand A tires that punctured was compared to the proportion of Brand B tires that punctured. Is this a good experimental design? (A) No, because more than two tire brands should be used (B) No, because there might not be enough tires that puncture during the experiment (C) No, because of the presence of confounding (D) No, because proportions are not appropriate statistics to compare (E) Yes

A tire manufacturer has a 60,000-mile warranty for tread life. The manufacturer considers the overall tire quality to be acceptable if less than 8% are worn out at 60,000 miles.The manufacturer tests 250 tires that have been used for 60,000 miles. They find that 15 of them are worn out. With this data, we test the following hypotheses at the 5% significance level.H0: The proportion of tires that are worn out after 60,000 miles is equal to 0.08.Ha: The proportion of tires that are worn out after 60,000 miles is less than 0.08.The p-value is 0.15. Which conclusion is correct? Reject H0. Fail to reject H0. Accept H0.

Technician A says tires are available in a variety of tread patterns. Technician B says tread wear indicators are used to improve tire wear. Which technician is correct?

1. A tyre dealer received samples of tyres from two suppliers X and Y. Hehad the samples tested for length of life (in months) with the followingresults:Length of LifeSupplier P: Supplier Q:(in Months):4-88-1212-1616-201021642301244Find the answers for the following questions:a. Which of the two tyres has a greater average life?b. Which of the two tyres is better do you prefer to buy?