For the year 2010, 33% of taxpayers with adjusted gross incomes between $30,000
ID: 3060926 • Letter: F
Question
For the year 2010, 33% of taxpayers with adjusted gross incomes between $30,000 and $60,000 itemized deductions on their federal income tax return (The Wall Street Journal, October 25, 2012). The mean amount of deductions for this population of taxpayers was 26, $16.642. Assume the standard deviation is $2400. What is the probability that a sample of taxpayers from this income group who have itemized deductions will show a sample mean within $200 of the population mean for a. each of the following sample sizes: 30, 50, 100, and 400? b. What is the advantage of a larger sample size when attempting to estimate the popu- lation mean?Explanation / Answer
a)
(i)
(ii)
(iii)
(iv)
b) advantage of having large sample is that there is higher probability tht sample will remain with in a smaller margin of error from population mean,
for normal distribution z score =(X-)/ here mean= = 16642 std deviation == 2400.0000