Discrete Random Variables
A collection of videos, activities and worksheets that are suitable for A Level Maths.
What is the meaning of Var(X) and how to calculate it for a discrete random variable?
The Expected Mean E(X)
The meaning of this function, Expected Mean E(X), and how to use it to calculate the expected mean for a discrete random variable.
Extending E(X) to E(X ± a) and E(aX)
What these functions mean, and how to use them.
Variance : Var(X)
The meaning of Var(X) and how to calculate it for a discrete random variable.
Extending Var(X) to Var(X ± a) and Var(aX)
I show you what these functions mean, and how to use them.
Why does Var(a)=0, Var(X ± a) = Var(X) and Var(aX) = a2Var(X)?
Non formal proof of these results.
The meaning and calculation of E(X2)
In this tutorial I show you the meaning of this function and how to calculate it for a discrete random variable.
Check out our most popular games!
Fraction Concoction Game:
Master fractions in the lab: mix, add, and subtract beakers to create the perfect concoction!
Fact Family Game:
Complete fact families and master the link between addition & subtraction and multiplication & division.
Number Bond Garden:
Clear the board by matching number pairs that sum to ten in this garden-themed mental math puzzle.
Online Addition Subtraction Game:
Practice your addition and subtraction skills to help the penguin find its mummy.
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