Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

The following is a simple random sample of textbook expenses of IUPUI students f

ID: 2507268 • Letter: T

Question

The following is a simple random sample of textbook expenses of IUPUI students for the Spring 2013 semester.

320 350 250 530 200 480 400


570 230 300 460 580 540 210


560 510 260 370 200 230 480


510 570 270 250 560 450 220


390 400 540 240 580 600 520


370 380 280 470 580 550 320


230 340 430 220 310 400 210
6 A 95% confidence interval for the mean textbook expenditure is $______, $______


(Note: Use the Excel functions to compute the mean and standard deviation. Otherwise, you'd be wasting your time. And, don't round anything, except the final answer.)
a 377.1 447.8






b 369.4 437.1






c 363.5 434.1






d 354.0 430.5
















7 In the previous question, to obtain a margin of error MOE = $20, the minimum sample size is n = _______.
Use the standard deviation from that sample (rounded to the nearest integer) as the planning value. a 170







b 144







c 100







d 71

















The following is a simple random sample of textbook expenses of IUPUI students for the Spring 2013 semester.

320 350 250 530 200 480 400


570 230 300 460 580 540 210


560 510 260 370 200 230 480


510 570 270 250 560 450 220


390 400 540 240 580 600 520


370 380 280 470 580 550 320


230 340 430 220 310 400 210
6 A 95% confidence interval for the mean textbook expenditure is $______, $______


(Note: Use the Excel functions to compute the mean and standard deviation. Otherwise, you'd be wasting your time. And, don't round anything, except the final answer.)
a 377.1 447.8






b 369.4 437.1






c 363.5 434.1






d 354.0 430.5
















7 In the previous question, to obtain a margin of error MOE = $20, the minimum sample size is n = _______.
Use the standard deviation from that sample (rounded to the nearest integer) as the planning value. a 170







b 144







c 100







d 71

















Explanation / Answer

6) mean = 392.24


sd dev = 131.68


mean lies between ( 392.24 - 1.96 * 131.68/sqrt(49) , 392.24 + 1.96 * 131.68)


= 354, 430.5





7) a = 170