Understanding Normal Distribution and Z-Scores

This video tutorial explains how to use a free online graphing calculator to determine normal distribution probabilities. It covers the concept of z-scores and the standard normal distribution, demonstrating how to calculate probabilities for different z-score intervals using the calculator's normal CDF function. The tutorial includes step-by-step examples and provides guidance on using the calculator's function reference.

What is a z-score in the context of a normal distribution?

• A measure of data variability

• A measure of central tendency

• A number of standard deviations a data value is from the mean

• A type of probability distribution

What are the mean and standard deviation of a standard normal distribution?

• Mean of 1 and standard deviation of 0

• Mean of 1 and standard deviation of 1

• Mean of 0 and standard deviation of 1

• Mean of 0 and standard deviation of 0

Which function is used in the calculator to determine normal distribution probabilities?

• normal CDF

• normal PDF

• normal SDF

• normal IDF

When calculating the probability that Z is greater than 0.2, what is the exaggerated upper bound used?

• 1000

• 99999

• 9999

• 100000

What is the approximate probability that Z is greater than 0.2?

• 0.136

• 0.421

• 0.500

• 0.896

For finding the probability that Z is less than -1.1, what is the exaggerated lower bound used?

• -9999

• -99999

• -100000

• -1000

What is the approximate probability that Z is less than -1.1?

• 0.421

• 0.136

• 0.896

• 0.500

In the example where Z is between -2 and 1.4, what is the approximate probability?

• 0.500

• 0.896

• 0.136

• 0.421

What is the purpose of the normal CDF function in the calculator?

• To plot a normal distribution graph

• To find the probability of a z-score within a specified range

• To calculate the mean of a data set

• To determine the standard deviation of a data set

Where can you find the normal CDF function in the calculator?

• In the main toolbar

• Under the help menu, in function references

• In the settings menu

• Under the graphing menu