Question

The shape of the distribution of the time required to get an oil change at a 10-minute oil-change facility is unknown. However, records indicate that the mean time is 11.4 minutes, and the standard deviation is 4.3 minutes. (a) To compute probabilities regarding the sample mean using the normal model, what size sample would be required? (b) What is the probability that a random sample on n=35 oil changes results in a sample mean time less than 10 minutes?

Name: the shape of the distribution of the time required to get an oil change at a 10 minute oil change facility is unknown however records indicate that the mean time is 114 minutes and the stand 56746
Uploaded: 2021-12-10T02:40:33-08:00
Duration: 3 min 30 s
Channel: David Nguyen
Description: the shape of the distribution of the time required to get an oil change at a 10 minute oil change facility is unknown however records indicate that the mean time is 114 minutes and the stand 56746

          The shape of the distribution of the time required to get an oil
change at a 10-minute oil-change facility is unknown. However,
records indicate that the mean time is 11.4 minutes, and the
standard deviation is 4.3 minutes.
(a) To compute probabilities regarding the sample mean using the
normal model, what size sample would be required?
(b) What is the probability that a random sample on n=35 oil
changes results in a sample mean time less than 10 minutes?

Added by Joseph A.

Elementary Statistics a Step by Step Approach

Allan G. Bluman 9th Edition

Instant Answer

Solved by Expert David Nguyen

12/10/2021

Step 1

Step 1: To compute probabilities regarding the sample mean using the normal model, the sample size required should be greater than or equal to 30 according to the central limit theorem. Show more…

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The shape of the distribution of the time required to get an oil change at a 10-minute oil-change facility is unknown. However, records indicate that the mean time is 11.4 minutes, and the standard deviation is 4.3 minutes. (a) To compute probabilities regarding the sample mean using the normal model, what size sample would be required? (b) What is the probability that a random sample on n=35 oil changes results in a sample mean time less than 10 minutes?