Question

A population has a mean of 161.2 and a standard deviation of 9.6. A sample of size 13 is taken from this population. What is the standard deviation of the sampling distribution of the mean?  Enter your answer to 3 decimal places.

We have two random variables, A and B. A has a mean of 89.6 and a standard deviation of 37.7. B has a mean of 23.6 and a standard deviation of 15.1. If we create a new random variable C, defined as C= A + B, what is the mean of C? Enter your answer as a decimal to one decimal place.

A random variable A has a mean of 74.2 and a variance of 16.7. A second random variable B is created by scaling A, such that, B = 9A. What is the mean of the random variable B. Enter you answer to 1 decimal place.   

We have two random variables, A and B. A has a mean of 51.1 and a standard deviation of 32.5. B has a mean of 26.2 and a standard deviation of 13.1. If we create a new random variable C, defined as C= A + B, what is the standard deviation of C? Enter your answer as a decimal to one decimal place.

A population has a mean of 317 and a standard deviation of 161. If a sample of size 6 is taken, what is the probability the sample mean is greater than 446.1? Enter your answer as a decimal to 3 decimal places.

A population has a mean of 220 and a standard deviation of 120. If a sample of size 6 is taken, what is the probability the sample mean is greater than 291.6? Enter your answer as a decimal to 3 decimal places.

Answer 1