Statistics

A student scores 85 on a test with a mean of 75 and a standard deviation of 5. Find the student's z-score.

A study reports a correlation coefficient of r = -0.82 between two quantitative variables. Describe the direction and strength of the linear relationship.

Find the mean of the data set: 8, 12, 15, 10, 5.

Find the median and mode of the data set: 4, 7, 9, 7, 12, 5, 7.

Find the population variance and population standard deviation of the data set: 2, 4, 6, 8.

Find the range and interquartile range (IQR) of the data set: 2, 4, 6, 8, 10, 12, 14.

For a binomial random variable with n = 20 and p = 0.30, find the mean and standard deviation.

For a regression model, the actual value of y is 52 and the predicted value is ŷ = 47. Find the residual and interpret its sign.

The scores on an exam are normally distributed with a mean of 70 and a standard deviation of 8. Approximately what percentage of scores fall between 62 and 78?

Two fair coins are tossed. What is the probability of getting exactly one head?