Understanding Normal Distribution and Inverse Norm

The video tutorial explains how to find the value of x in a normally distributed random variable where the probability of x being less than a certain value is 25%. It introduces the concept of normal and standard normal distributions, and demonstrates how to use the TI-84 calculator's inverse norm feature to calculate the value of c. The tutorial concludes with the calculation of c, showing that the probability of x being less than approximately 69.6 is 25%.

What is the mean of the normally distributed random variable x in the given problem?

• 65

• 75

• 95

• 85

What is the probability of x being less than c in the given problem?

• 0.15

• 0.25

• 0.35

• 0.45

Tags

CCSS.6.SP.A.3

In a standard normal distribution, what is the mean?

• 8

• 75

• 1

• 0

Tags

CCSS.HSS.ID.A.4

Which feature on the TI-84 calculator is used to find the value of c?

• Normal PDF

• Normal CDF

• Inverse Norm

• Standard Deviation

Tags

CCSS.HSS.ID.A.4

What is the first step in using the TI-84 calculator to find the value of c?

• Enter the mean

• Enter the standard deviation

• Enter the probability

• Press second-vars for the distribution menu

Tags

CCSS.HSS.ID.A.4

What is the calculated value of c where the probability of x being less than c is 25%?

• 71.2

• 67.8

• 69.6

• 65.4

What does the calculated value of c represent in terms of probability?

• The probability of x being more than 75

• The probability of x being less than c

• The probability of x being equal to c

• The probability of x being greater than c