Random variable

A random variable is a rule that assigns a numerical value to each outcome in a sample space, or it can be defined as a variable whose value is unknown or a function that gives numerical values to each of an experiment's outcomes.

1. What is variable and random variable?
2. How do you identify a random variable?
3. What are the two types of random variables?
4. Why random variable is called so?

What is variable and random variable?

A variable is a symbol that represents some quantity. A variable is useful in mathematics because you can prove something without assuming the value of a variable and hence make a general statement over a range of values for that variable. A random variable is a value that follows some probability distribution.

How do you identify a random variable?

If you see a lowercase x or y, that's the kind of variable you're used to in algebra. It refers to an unknown quantity or quantities. If you see an uppercase X or Y, that's a random variable and it usually refers to the probability of getting a certain outcome.

What are the two types of random variables?

Random variables are classified into discrete and continuous variables. The main difference between the two categories is the type of possible values that each variable can take.

Why random variable is called so?

So the random variables are called random because the value of this variable cannot be defined with certainty, we can only make a guess and this guess is called the probability of having a particular value of a random variable. In coin toss experiment, P(X=1) = 0.5.