Question

In: Statistics and Probability

A sample of 36 dishwashers yields a mean replacement time of 11.5 years. Given that σ...

A sample of 36 dishwashers yields a mean replacement time of 11.5 years. Given that σ =2.6, find the margin of error in estimating μ at the 98% level of confidence. Round to one decimal place.

Solutions

Expert Solution

Solution :

Given that,

Point estimate = sample mean =   = =11.5

Population standard deviation =    =2.6

Sample size = n =36

At 98% confidence level the z is ,

= 1 - 98% = 1 - 0.98 = 0.02

/ 2 = 0.02/ 2 = 0.01

Z/2 = Z0.01 = 2.326 ( Using z table    )

Margin of error = E = Z/2    * ( /n)

= 2.326 * ( 2.6 /  36 )

= 1.0079

=1.0


Related Solutions

The mean replacement time for a random sample of 15 washing machine is 10.7 years and...
The mean replacement time for a random sample of 15 washing machine is 10.7 years and the standard deviation is 2.5 years. Construct 98% confidence interval for the standard deviation of the replacement of all washing machines of this type. What would be the value if the standard deviation is 2.7 years.
You conduct an experiment on 36 subjects which yields a sample mean of 35 with a...
You conduct an experiment on 36 subjects which yields a sample mean of 35 with a standard deviation of 5. Using that data, what is the 95% Confidence Interval for the mean of your sample’s population? Describe the difference between statistical significance and effect size. How is each used in describing the results of an experiment? What is Statistical Power? What are 3 ways of increasing power in an experiment? Explain why each method increases statistical power
The mean and standard deviation for the charge time of a random sample of 36 iPhones...
The mean and standard deviation for the charge time of a random sample of 36 iPhones were found to be 23 and 2.5 hours respectively. Assuming that the charge time was normally distributed. A 99% confidence interval for the mean charge time is: Select one: a. 23 +/- 1.29 b. 23 +/- 1.40 c. 23 +/- 0.77 d. 23 +/- 1.14 e. 23 +/- 0.91
Replacement time for TV sets are normally distributed with a mean of 7.2 years and a...
Replacement time for TV sets are normally distributed with a mean of 7.2 years and a standard deviation of 1.1 years. A) Find the probability that a randomly selected TV will have a replacement time less than 5.0 years. B) If you want to provide a warranty so that only 1% of the TV sets will be replaced before the warranty expires, what is the length of the warranty? I am unfamiliar with using a Stand Normal Distribution chart, if...
Let's assume that your process yields products with a mean diameter of 1.251mm with σ =...
Let's assume that your process yields products with a mean diameter of 1.251mm with σ = 0.00083mm. The Process Specification call for a LSL=1.245mm and USL=1.255. What is the Cpk? You are a consultant to an manufacturing company that wants to design a control chart to monitor the parts quality sourced from a supplier. The supplier guarantees an average of only 4 blemishes per part. What is the three-sigma (standard deviation) LCL control chart limit (blemishes per part)? Over the...
A sample of size 20 yields a sample mean of 23.5 and a sample standard deviation...
A sample of size 20 yields a sample mean of 23.5 and a sample standard deviation of 4.3. Test HO: Mean >_ 25 at alpha = 0.10. HA: Mean < 25. This is a one-tailed test with lower reject region bounded by a negative critical value.
Use the sample information x⎯⎯ = 36, σ = 6, n = 11 to calculate the...
Use the sample information x⎯⎯ = 36, σ = 6, n = 11 to calculate the following confidence intervals for μ assuming the sample is from a normal population. (a) 90 percent confidence. (Round your answers to 4 decimal places.) The 90% confidence interval is from to? (b) 95 percent confidence. (Round your answers to 4 decimal places.) The 95% confidence interval is from to ? c) 99 percent confidence. (Round your answers to 4 decimal places.) The 99% confidence...
Let's assume your process yields products with a mean diameter of 12.50mm and σ = 0.010mm....
Let's assume your process yields products with a mean diameter of 12.50mm and σ = 0.010mm. If the specification calls for a range of 12.480mm - 12.530mm, what percentage of parts will have a diameter within these limits?
A company claims its employees' mean age is 36 years old. A simple random sample of...
A company claims its employees' mean age is 36 years old. A simple random sample of 40 employees is taken, and is found to have a sample mean of 35.8 years, and sample deviation of 2.2 years. a. construct and interpret a 98% confidence interval estimate of the true population mean age. b. do you think the company's claimed mean is reasonable, based on your answer to part A? Why? c. if we assume population mean is 36, as claimed,...
Suppose x has a normal distribution with mean μ = 36 and standard deviation σ =...
Suppose x has a normal distribution with mean μ = 36 and standard deviation σ = 5. Describe the distribution of x values for sample size n = 4. (Round σx to two decimal places.) μx = σx = Describe the distribution of x values for sample size n = 16. (Round σx to two decimal places.) μx = σx = Describe the distribution of x values for sample size n = 100. (Round σx to two decimal places.) μx...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT