Probability and IQ Score Analysis

The video tutorial explains how to calculate probabilities for different IQ scores using a normal distribution with a mean of 100 and a standard deviation of 15. It demonstrates using a TI-84 calculator to find probabilities for IQ scores greater than 90, less than 120, and less than 105, as well as calculating the number of people in a sample with IQs less than 105 and greater than 135.

What is the mean IQ score in a normal distribution?

• 90

• 100

• 120

• 110

Which tool is used on the TI-84 calculator to find the probability of an IQ greater than 90?

• Z-Score Table

• Normal CDF

• Normal PDF

• Empirical Rule

What is the probability of having an IQ greater than 90?

• 0.0098

• 0.6306

• 0.9088

• 0.7475

To find the probability of an IQ less than 120, what is exaggerated in the calculator?

• Mean

• Lower bound

• Upper bound

• Standard deviation

What is the probability of having an IQ less than 120?

• 0.7475

• 0.6306

• 0.9088

• 0.0098

How many people in a sample of 1200 are expected to have an IQ less than 105?

• 908

• 120

• 757

• 630

What is the probability of having an IQ less than 105?

• 0.7475

• 0.0098

• 0.6306

• 0.9088

In a sample of 600, how many people are expected to have an IQ greater than 135?

• 60

• 120

• 135

• 6

What is the probability of having an IQ greater than 135?

• 0.0098

• 0.6306

• 0.9088

• 0.7475

What is the exaggerated upper bound used to find the probability of an IQ greater than 135?

• 999

• 999999

• 9999

• 99999