Question

A random sample of size 65 has sample mean 78 and sample standard deviation 7.5. Find...

A random sample of size 65 has sample mean 78 and sample standard deviation 7.5. Find a 98% confidence interval for µ.

Math   Statistics-And-Probability   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

A random sample of size 65 has sample mean 78 and sample standard deviation 7.5. Find a 98% confidence interval for µ.

Table value t at 65-1 = 64 DF is 2.3860

98% CI =(75.7804, 80.2196)

Confidence Interval Estimate for the Mean

Data

Sample Standard Deviation

7.5

Sample Mean

78

Sample Size

65

Confidence Level

98%

Intermediate Calculations

Standard Error of the Mean

0.9303

Degrees of Freedom

64

t Value

2.3860

Interval Half Width

2.2196

Confidence Interval

Interval Lower Limit

75.7804

Interval Upper Limit

80.2196
0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
A random sample of size 36 has sample mean 12 and sample standard deviation 3. (a)...
A random sample of size 36 has sample mean 12 and sample standard deviation 3. (a) Check Requirements: Is it appropriate to use a Student’s t distribution to compute a confidence interval for the population mean ? Explain. (b) Find a 80% confidence interval for µ. [round E to 2 d.p.] (c) Interpretation: Explain the meaning of the confidence interval you computed.
A population has a mean μ=78 and a standard deviation σ=22. Find the mean and standard...
A population has a mean μ=78 and a standard deviation σ=22. Find the mean and standard deviation of a sampling distribution of sample means with sample size n=264. μx= ?????
A simple random sample of size 17 has mean x̄ = 8.44 and standard deviation s...
A simple random sample of size 17 has mean x̄ = 8.44 and standard deviation s = 5.38. The population is normally distributed. Construct a 95% confidence interval for the population standard deviation.
A random variable ?x has a Normal distribution with an unknown mean and a standard deviation...
A random variable ?x has a Normal distribution with an unknown mean and a standard deviation of 12. Suppose that we take a random sample of size ?=36n=36 and find a sample mean of ?¯=98x¯=98 . What is a 95% confidence interval for the mean of ?x ? (96.355,99.645)(96.355,99.645) (97.347,98.653)(97.347,98.653) (94.08,101.92)(94.08,101.92) (74.48,121.52)
Random samples of size 78 were selected from a population with mean 137 and standard deviation...
Random samples of size 78 were selected from a population with mean 137 and standard deviation 4.2. A.) What is the mean of the sample means (  x )? B.) What is the standard deviation of the sample means (  x )?
Random samples of size 78 were selected from a population with mean 137 and standard deviation...
Random samples of size 78 were selected from a population with mean 137 and standard deviation 4.2. A.) What is the mean of the sample means (  x )? B.) What is the standard deviation of the sample means (  x )?
A simple random sample of size n is drawn. The sample mean is found to be...
A simple random sample of size n is drawn. The sample mean is found to be 35.1, and the sample standard deviation is found to be 8.7. a. Construct the 90% confidence interval if the sample size is 40. b. Construct the 98% confidence interval if the sample size is 40. c.How does increasing the level of confidence affect the size of the margin of error? d. Would you be able to compute the confidence intervals if the sample size...
a.)A normal random variable X has unknown mean μ and standard deviation σ = 6. What...
a.)A normal random variable X has unknown mean μ and standard deviation σ = 6. What is the margin of error E for a 98 percent confidence interval for μ, based on a random sample of size b.)(b) What sample size would be needed in part (a) to have a margin of error
Suppose x has a mound-shaped distribution. A random sample of size 16 has sample mean 10...
Suppose x has a mound-shaped distribution. A random sample of size 16 has sample mean 10 and sample standard deviation 2. (b) Find a 90% confidence interval for μ (c) Interpretation Explain the meaning of the confidence interval you computed.
A study based on a random sample of 17 reported a sample mean of 65 with...
A study based on a random sample of 17 reported a sample mean of 65 with a sample standard deviation of 4. Calculate a 95% Confidence interval. What is the margin of error? If we calculated a 90% confidence interval, as compared to your answer in part b, would your margin of error increase: (choose one) increase decrease stay the same If we increase the sample size to 50 persons, but the reported sample mean and sample standard deviation stayed...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT