Question

A random sample of 42 college graduates revealed that they worked an average of 7.4 years on the job before being promoted. The sample standard deviation was 3.0 years. Using the 0.99 degree of confidence, what is the confidence interval for the population mean? a) 3.22 and 12.37 b) 6.17 and 8.63 c) 5.51 and 9.29 d) 6.15 and 8.65

Name: a random sample of 42 college graduates revealed that they worked an average of 74 years on the job before being promoted the sample standard deviation was 30 years using the 099 degree of confidence
Uploaded: 2023-08-21T05:20:59-08:00
Duration: 1 min 23 s
Channel: Qudsiya Anis
Description: a random sample of 42 college graduates revealed that they worked an average of 74 years on the job before being promoted the sample standard deviation was 30 years using the 099 degree of confidence

          A random sample of 42 college graduates revealed that they worked an average of 7.4 years on the job before being promoted. The sample standard deviation was 3.0 years. Using the 0.99 degree of confidence, what is the confidence interval for the population mean?

a) 3.22 and 12.37
b) 6.17 and 8.63
c) 5.51 and 9.29
d) 6.15 and 8.65

Added by Nostalgic B.

Elementary Statistics a Step by Step Approach

Allan G. Bluman 9th Edition

Instant Answer

Solved by Expert Qudsiya Anis

08/21/2023

Step 1

The formula for the standard error of the mean is the standard deviation divided by the square root of the sample size. In this case, the standard deviation is 3.0 years and the sample size is 42. So, the standard error of the mean is 3.0 / sqrt(42) = 0.46 years. Show more…

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A random sample of 42 college graduates revealed that they worked an average of 7.4 years on the job before being promoted. The sample standard deviation was 3.0 years. Using the 0.99 degree of confidence, what is the confidence interval for the population mean? a) 3.22 and 12.37 b) 6.17 and 8.63 c) 5.51 and 9.29 d) 6.15 and 8.65