For students at a large, state university, consider two groups. Group 1: Student
ID: 3153303 • Letter: F
Question
For students at a large, state university, consider two groups. Group 1: Students who purchased their textbooks for the current semester at the campus bookstore and Group 2: Students who purchased their textbooks for the current semester online. A 99% confidence interval for 12, the difference in population mean amounts spent on textbooks, is 30 to 60 dollars.
1. The confidence interval would tend to support the claim that, on average, students who purchased their books at the campus bookstore spent __________ dollars more than those who purchased their books online. A. at most 40 B. less than 20 C. at least 25 D. more than 65 E. at least 32 2. The confidence interval provides no strong evidence to support or refute the claim that, on average, students who purchased their books at the campus bookstore spent __________ dollars more than those who purchased their books online.
A. more than 25 B. more than 50 C. at most 70 D. less than 65 E. at least 20
Explanation / Answer
1. The confidence interval would tend to support the claim that, on average, students who purchased their books at the campus bookstore spent __________ dollars more than those who purchased their books online.
As the interval is 30 to 60 dollars, then the only claim suppported is, as this is totally greater than 25,
C. at least 25 [ANSWER, C]
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2. The confidence interval provides no strong evidence to support or refute the claim that, on average, students who purchased their books at the campus bookstore spent __________ dollars more than those who purchased their books online.
Hence, we need a number inside the interval, as there is no strong evidence. Hence,
B. more than 50 [ANSWER, B]