The Wall Street Journal reported that 33% of taxpayers with adjusted gross incomes between 30,000 and 60,000 itemized deductions on their federal income tax return. The mean amount of deductions for this population of taxpayers was $17,545 . Assume that the standard deviation is $2,160. Use z-table.
a. What is the probability that a sample of taxpayers from this income group who have itemized deductions will show a sample mean within $210 of the population mean for each of the following sample sizes: 30, 50, 100 and 400? Round your answers to four decimals.
n= 30
n= 50
n= 100
n= 400
b. What is the advantage of a larger sample size when attempting to estimate the population mean? Round your answers to four decimals.
The probability that the sample mean will be within a specified distance of the population mean. In the automobile insurance example, the probability of being within +-210 of U ranges from BLANK for a sample of size 30 to BLANK for a sample of size 400 .
Expert Answer
0.4056 0.5082 0.6690 0.9482 A large sample the probabili…View the full answer