Lesson: Standard Deviation and Variance of Discrete Random Variables

In this lesson, we will learn how to calculate the variance and standard deviation of a probability distribution.

Video

09:30

Sample Question Videos

  • 01:11
  • 04:30
  • 03:29

Worksheet: 25 Questions • 4 Videos

Q1:

The function in the given table is a probability function of a discrete random variable 𝑋. Find the standard deviation of 𝑋. Give your answer to two decimal places.

𝑥 − 5 − 4 − 3 − 1
𝑓 ( 𝑥 ) 1 3 1 8 1 4 7 2 4

Q2:

The function in the given table is a probability function of a discrete random variable 𝑋. Find the standard deviation of 𝑋. Give your answer to two decimal places.

𝑥 4 6 10
𝑓 ( 𝑥 ) 8 1 9 8 1 9 3 1 9

Q3:

The function in the given table is a probability function of a discrete random variable 𝑋. Given that the expected value of 𝑋 is 6.5, find the standard deviation of 𝑋. Give your answer to two decimal places.

𝑥 3 𝐴 6 8
𝑓 ( 𝑥 ) 0.2 0.1 0.1 0.6
Preview Download

Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.