Statistics: Probability and Descriptive Measures

This video tutorial demonstrates how to use the normal distribution calculator from onlinestatbook.com to determine probabilities for various test score intervals. It covers calculating probabilities for scores greater than 90, less than 70, between 65 and 82, and outside 65 and 85, using a dataset with a mean of 75 and a standard deviation of 8.2. The tutorial provides step-by-step instructions on entering data into the calculator and interpreting the results, including converting probabilities to percentages.

What is the mean of the test scores in the given problem?

• 70

• 75

• 80

• 85

What is the standard deviation of the test scores in the given problem?

• 8.2

• 8.0

• 8.5

• 7.5

Which option should be selected in the calculator to find the probability of a score greater than 90?

• Between

• Outside

• Above

• Below

What is the probability that a test score is greater than 90?

• 0.271

• 0.692

• 0.034

• 0.223

Which option should be selected in the calculator to find the probability of a score less than 70?

• Outside

• Below

• Between

• Above

What is the probability that a test score is less than 70?

• 0.223

• 0.271

• 0.034

• 0.692

Which option should be selected in the calculator to find the probability of a score between 65 and 82?

• Outside

• Above

• Below

• Between

What is the probability that a test score is between 65 and 82?

• 0.034

• 0.271

• 0.223

• 0.692

Which option should be selected in the calculator to find the probability of a score less than 65 or greater than 85?

• Below

• Above

• Between

• Outside

What is the probability that a test score is less than 65 or greater than 85?

• 0.034

• 0.271

• 0.692

• 0.223