A hybrid course is one that contains both online and classroom instruction. In a study performed at Middle Georgia State University, a software package was used as the main souce of instruction in a hybrid college algebra course. The software tracked the number of hours it took for each student to meet the objectives of the course. In a sample of 45 students, the mean number of hours was 80.5, with a standard deviation of 51.2. a. Construct a 95% confidence interval for the mean number of hours it takes for a student to meet the course objectives.

Question
Upper level algebra
asked 2020-11-08
A hybrid course is one that contains both online and classroom instruction. In a study performed at Middle Georgia State University, a software package was used as the main souce of instruction in a hybrid college algebra course. The software tracked the number of hours it took for each student to meet the objectives of the course. In a sample of 45 students, the mean number of hours was 80.5, with a standard deviation of 51.2.
a. Construct a 95% confidence interval for the mean number of hours it takes for a student to meet the course objectives.

Answers (1)

2020-11-09
(a)Step 1
A.95% confidence interval for the mean number of hours it takes for the student to makes course of objectives is, First, compute f-critical value then find confidence interval.
The t critical value for the 95% confidence interval is,
\(\alpha=0.05\)
The sample size is small and two-tailed test. Look in the column headed and the row headed in the fdistribution table by using degree of freedom is,
d.f.=n-1
=45-1=44
The tcritical value for the 95% confidence interval is 2.015.
Step 2
\(95\% C.I.=\overline{x}\pm t_{c}\times s / \sqrt{n}\)
\(=80.50\pm2.015\times51.20/\sqrt{45}\)
\(=80.50\pm 15.38\)
= 65.12 to 95.88
65.12 to 95.884 95% confidence interval for the mean number of hours it takes for the student to makes course of objectives is.
Step 3
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