Question

Which sample size will have the least variability in the sampling distribution of the sample mean when determining the true mean number of days for tire tread wear to reach 2 mm?

a) 35
b) 55
c) 25
d) 45

Answer 1

The sample size of 55 will have the least variability in the sampling distribution of the sample mean when compared to the options of 35, 25, and 45.

Step-by-step explanation:

The student is asking about the variability in the sampling distribution of the sample mean, which is related to determining the true mean number of days for tire tread wear to reach 2 mm. Variability in the sampling distribution of the sample mean decreases as the sample size increases. This is because a larger sample size will more closely approximate the population mean and have a smaller standard error. Therefore, among the given options, sample size 55 will have the least variability in the sampling distribution of the sample mean (options are 35, 55, 25, 45).