# Question

When a production machine is properly calibrated, it requires an average of 25 seconds per unit produced, with a standard deviation of 3 seconds. For a simple random sample of n = 36 units, the sample mean is found to be x-bar = 26.2 seconds per unit.

a. What z-score corresponds to the sample mean of x-bar = 26.2 seconds?

b. When the machine is properly calibrated, what is the probability that the mean for a simple random sample of this size will be at least 26.2 seconds?

c. Based on the probability determined in part (b), does it seem likely that the machine is properly calibrated? Explain your reasoning.

a. What z-score corresponds to the sample mean of x-bar = 26.2 seconds?

b. When the machine is properly calibrated, what is the probability that the mean for a simple random sample of this size will be at least 26.2 seconds?

c. Based on the probability determined in part (b), does it seem likely that the machine is properly calibrated? Explain your reasoning.

## Answer to relevant Questions

For a given sample size, the standard error of the sample mean is 10 grams. With other factors unchanged, to what extent must the sample size be increased if the standard error of the sample mean is to be just 5 grams? Of 500 vehicles sold by an auto dealership last month, 200 have a defect that will require a factory recall for dealer correction. For a simple random sample of n 5 50 of last month’s customers, what is the probability ...A random variable is normally distributed with mean μ = $1500 and standard deviation σ = $100. Determine the standard error of the sampling distribution of the mean for simple random samples with the following sample ...The Colgate-Palmolive Company has 36,600 employees. If the company wishes to estimate, within 2 percentage points and with 99% confidence, the percentage of employees who are interested in participating in a new stock option ...To avoid losing part of their federal highway fund allocation, state safety administrators must ensure that interstate speed limits are adequately enforced within their state. In an upcoming test, federal researchers will be ...Post your question

0