12. The director of admissions at the University of Maryland, University College is concerned about the high cost of textbooks for the students each semester. A sample of 25 students enrolled in the university indicates that x(bar)=$315.40 and s=$43.20.
Using a significance level of 0.1, what are the boundaries of the confidence interval?
a. 302.438 - 326.184
b. 300.618 – 330.182
c. 297.485 – 327.820
d. 282.871 – 338.475
13. The director of admissions at the University of Maryland, University College is concerned about the high cost of textbooks for the students each semester. A sample of 25 students enrolled in the university indicates that x(bar)=$315.40 and s=$43.20.
A mean that is not in a confidence interval is rejected by the confidence interval, and we say the evidence against the mean is significant. At the 0.10 level of significance, is there evidence against mean $300?
a. No, because 300 is below the lower limit of the confidence interval.
b. Yes, because 300 is below the lower limit of the confidence interval.
c. No, because 300 is in the confidence interval.
d. Yes, because 300 is in the confidence interval.
14. The director of admissions at the University of Maryland, University College is concerned about the high cost of textbooks for the students each semester. A sample of 25 students enrolled in the university indicates that x(bar)=$315.40 and s=$75. (Note the sample standard deviation is different from the first part).
A mean that is in a confidence interval is not rejected by the confidence interval, and we say the evidence against the mean is not significant. At the 0.05 level of significance, is there evidence against mean $300?
a. No, because 300 is below the lower limit of the confidence interval.
b. Yes, because 300 is below the lower limit of the confidence interval
c. No, because 300 is in the confidence interval
d. Yes, because 300 is in the confidence interval
12. The director of admissions at the University of Maryland, University College is concerned about the...
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