1. A random sample of 42 textbooks has a mean price of $114
A random sample of 42 textbooks has a mean price of $ and a standard deviation of $12.30.
Find a point estimate for the mean price of all textbooks.
$42
$12.30
$114.50
$2.73

2. A random sample of 42 textbooks has a mean price of $114
A random sample of 42 textbooks has a mean price of $ and a standard deviation of $12.30.
Find a point estimate for the mean price of all textbooks.
$42
$12.30
$114.50
$2.73

3. Find the critical value zc necessary to form a 98% confidence interval.
2.33
2.05
0.5040
0.8365

4. Find the critical value zc necessary to form a 98% confidence interval.
2.33
2.05
0.5040
0.8365

5. A random sample of 42 textbooks has a mean price of $114
A random sample of 42 textbooks has a mean price of $ and a standard deviation of $12.30.
Find a 98% confidence interval for the mean price of all textbooks.
(111.38, )
(110.08, )
(110.78, )
(109.61, )

6. A random sample of 42 textbooks has a mean price of $114
A random sample of 42 textbooks has a mean price of $ and a standard deviation of $12.30.
Find a 98% confidence interval for the mean price of all textbooks.
(111.38, )
(110.08, )
(110.78, )
(109.61, )

7. Determine the minimum sample size needed to construct a 95% confidence interval for the mean age of employees at a company. The estimate must be accurate to within 0.5 year. Assume the standard deviation is 4.8 years. 18 19
354
355

8. Determine the minimum sample size needed to construct a 95% confidence interval for the mean age of employees at a company. The estimate must be accurate to within 0.5 year. Assume the standard deviation is 4.8 years. 18 19
354
355

9. Find the critical value tc necessary to form a 95% confidence interval with a sample size of 15.
1.960
2.145
2.131
2.120

10. Find the critical value tc necessary to form a 95% confidence interval with a sample size of 15.
1.960
2.145
2.131
2.120

11. A random sample of 15 DVD players has a mean price of $64
A random sample of 15 DVD players has a mean price of $64.30 and a standard deviation of $5.60.
Find a 95% confidence interval for the mean price of all DVD players.
(61.20, 67.40)
(61.47, 67.13)
(61.22, 67.38)
(61.10, 67.51)

12. A random sample of 15 DVD players has a mean price of $64
A random sample of 15 DVD players has a mean price of $64.30 and a standard deviation of $5.60.
Find a 95% confidence interval for the mean price of all DVD players.
(61.20, 67.40)
(61.47, 67.13)
(61.22, 67.38)
(61.10, 67.51)