# statistics

posted by .

In a survey randomly selected subjects, the mean age of the 36 respondents is 40.0 years and the standard deviation of the ages is 10.0 years. Use these sample results to construct a 95% confidence interval estimate of the mean age of the population from which the sample was selected.

• statistics -

95% confidence means that you will have 5% left in the two tails. Split this number in half to get .025 in each tail.
This is equivalent to a z-score of 1.96

Use this z-score in the formula to find the confidence interval.

## Similar Questions

1. ### elizabeth high school

. An admissions director wants to estimate the mean age of all students enrolled at a college. The estimate must be within one year of the population mean. Assume the population of ages is normally distributed. Determine the minimum …
2. ### Statistics

An admissions director wants to estimate the mean age of all students enrolled at a college. The estimate must be within one year of the population mean. Assume the population of ages is normally distributed. Determine the minimum …
3. ### statistics

1.A magazine reported that 6% of Americans read the news paper while driving. 100 drivers are selected at random, find the probability that exactly 25 of them say they read the newspaper while driving.(normal binomial formula to solve) …
4. ### Statistics

These are the only ones that I am having problems with. Please help.. 8.You are given the sample mean and the sample standard deviation. Use this information to construct the 90% and the 95% confidence intervals for the population …
5. ### stats

The president of a large university wishes to estimate the average age of the students presently enrolled. From past studies, the standard deviation ó is known to be 2 years. A sample of 50 students is selected and the mean is found …
6. ### Math Statistics

5. Students in an introductory statistics class were asked to report the age of their mothers when they were born. Summary statistics include Sample size: 36 students Sample mean: 29.643 years Sample standard deviation: 4.564 years …
7. ### statistics

A group of 49 randomly selected construction workers has a mean age of 22.4 years with a standard deviation of 3.8. According to a recent survey, the mean age should be mu=21.9. Test this hypothesis by constructing a 98% confidence …
8. ### social statistics

a smoking researcher is interested in estimating the average age when cigarette smokers first began to smoke. Taking a random sample of 25, she determines a sample mean of 16.8 years and a sample deviation of 1.5 years. Construct a …
9. ### famu

Construct a 99% confidence interval for the population mean, ì. Assume the population has a normal distribution. A group of 19 randomly selected employees has a mean age of 22.4 years with a standard deviation of 3.8 years. Round …
10. ### statistics

Go to a local library; collect a sample of books consisting of the ages of book (based on copyright dates). Plan and describe the sampling procedure, then use the results to construct a confidence interval estimate of the mean age …

More Similar Questions