Mileage tests were conducted on a randomly selected sample of 100 newly developed automobile tires. The results showed that the average tread life was 50,000 miles with a standard deviation of 3,500 miles. What is the best estimate of the average tread life in miles for the entire population of these tires?
A) 50,000
B) 3,500
C) (50,000/100)
D) (3,500/100)

Question

Quizplus · Accepted Answer

The best estimate of the average tread life in miles for the entire population of these tires is the sample mean, which is 50,000 miles. This is because the sample is randomly selected and is large enough to be representative of the population. The standard deviation provides information about the variability of the sample, but it is not used to estimate the population mean. Similarly, dividing the sample mean or standard deviation by the sample size does not provide a better estimate of the population mean.

Mileage Tests Were Conducted on a Randomly Selected Sample of 100