A 50-volt battery must be between 55 and 45 volts when it leaves the factory. Two hundred samples of batteries via a subgroup size of 5 are used and yield an average charge of 49 volts with a range average of 2.5. What is the standard deviation?

Adult men have heights with a mean of 69.0 inches and a standard deviation of 2.8 inches. Find the z-score of a man 63.4 inches tall. (to 2 decimal places)

The standard deviation of pulse rates of adult males is less than 10  bpm. For a random sample of 144 adult​ males, the pulse rates have a standard deviation of  9.1 bpm. Find the value of the test statistic.

Adult men have heights with a mean of 69.0 inches and a standard deviation of 2.8 inches. Find the z-score of a man 62 inches tall. (round to 2 decimal places)

Adult men have heights with a mean of 69.0 inches and a standard deviation of 2.8 inches. Find the z-score of a man 61.7 inches tall. (to 2 decimal places)

It takes an average of 14.5 minutes for blood to begin clotting after an injury. An EMT wants to see if the average will increase if the patient is immediately told the truth about the injury. The EMT randomly selected 70 injured patients to immediately tell the truth about the injury and noticed that they averaged 16.3 minutes for their blood to begin clotting after their injury. Their standard deviation was 4.75 minutes. What can be concluded at the the α = 0.10 level of significance? a. For this study, we should use [Select an answer b. The null and alternative hypotheses would be: Ho: ? Select an answer H₁: ? Select an answer ✓ c. The test statistic ? = (please show your answer to 3 decimal places.) d. The p-value = (Please show your answer to 4 decimal places.) e. The p-value is ? ✓ a f. Based on this, we should [Select an answer the null hypothesis. g. Thus, the final conclusion is that ... O The data suggest the populaton mean is significantly greater than 14.5 at a = 0.10, so…

Adult men have heights with a mean of 69.0 inches and a standard deviation of 2.8 inches. Find the z-score of a man 63.4 inches tall. (to 2 decimal places)

Adult men have heights with a mean of 69.0 inches and a standard deviation of 2.8 inches. Find the z-score of a man 75.4 inches tall. (to 2 decimal places)

The time needed to find a parking space is normally distributed with a mean of 20 minutes and a standard deviation of 5.18 minutes. 90% of the time, it takes less than how many minutes to find a parking space?

A normal population has a mean  μ = 31 and standard deviation = 8. What proportion of the population is less than 29?