SOLUTION: How do I work these problems out? 1. A study of 40 people found that they could do on the average 15 pull ups with a standard deviation of .6. Find the 99% confidence interval f

Question 1063136: How do I work these problems out?
1. A study of 40 people found that they could do on the average 15 pull ups with a standard deviation of .6. Find the 99% confidence interval for the mean of the population.
2. A study of 50 pizza delivery workers found that they could make 6 deliveries per hour with a standard deviation of 1. Find the 95% confidence interval of the mean for all pizza delivery workers.
3. A random sample of 50 households showed that the average number of TVs in each household is 2.3 with a standard deviation of .4. Find the 90% confidence level for the average number of TVs in every household in the population.
4. A researcher revealed that the average number of people who have a driver's license out of a sample of 100 people is 1.5 with a standard deviation of .3. Find the 80% confidence interval for the mean of the population.
5. The following random sample was selected: 4, 6, 3, 5, 9, 3. Find the 95% confidence interval for the mean of the population.

6.In a sample of 35 high school seniors, 14 of them are attending college in the fall. Find the 95% confidence interval for the true proportion of high school seniors that will attend college in the fall from the population.

7. In a sample of 200 people, 76 people would rather work out at home than in a gym. Find the 99% confidence interval for the true proportion of people who would rather work out at home than in a gym for the entire population.
0.76 +/- (2.575)(√0.76)/(-0.24)/√200
0.71323264675
0.713 - .5/1000 = 0.7125 - .5/.0005 = 0.712
0.713 + .5/1000 = 0.7125 +.5/.0005 = 0.714
The 99% confidence interval is +/- 0.76.
71.2% - 71.4%

8. A study found that out of 300 people 60% of them prefer to eat hamburgers rather than hot dogs. Find the 95% confidence interval for the true proportion of people who prefer to eat hamburgers rather than hot dogs in the entire population.

Thank for your help in advance on these problems.

Answer by ikleyn(52858) (Show Source): You can put this solution on YOUR website!
.
One question per post, PLEASE.

It is an official RULE of this site.

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