AP Statistics Practice (Interactive)

A dataset has a mean of 50 and a standard deviation of 5. According to the empirical rule (68-95-99.7), approximately what percentage of the data falls between 45 and 55?

A fair six-sided die is rolled three times. What is the probability of getting at least one 6?

Two events A and B are such that P(A) = 0.4, P(B) = 0.5, and P(A and B) = 0.2. Are A and B independent?

A 95% confidence interval for a population mean is calculated as (12.3, 18.7). Which of the following is the correct interpretation of this interval?

In a hypothesis test with H0: mu = 100 and Ha: mu > 100, a researcher obtains a p-value of 0.03. Using a significance level of alpha = 0.05, what conclusion should be drawn?

A researcher wants to reduce the margin of error in a confidence interval for a population proportion. Which change would accomplish this?

A chi-square goodness-of-fit test is conducted with 5 categories. The calculated chi-square test statistic is 9.488. What is the approximate p-value?

A Type I error occurs when a researcher:

A least-squares regression line has the equation y-hat = 3.2 + 1.5x. If x increases by 2 units, by how much does the predicted value of y change?

In a regression analysis, the coefficient of determination r-squared = 0.81. Which of the following is the correct interpretation?