Random Variables and its Probability Distributions
Random Variables and its Probability Distributions: Overview
This topic covers concepts such as Probability Distribution of a Random Variable, Random Variable, Mean/Expectation of a Random Variable, Variance of a Random Variable, and Standard Deviation of a Random Variable.
Important Questions on Random Variables and its Probability Distributions
Following is the distribution function of a discrete random variable
Find

In a game, a man wins Rs. if he gets or on a throw of a fair die and loses Rs. for getting any other number on the die. If he decides to throw the die either till he gets a or a or to a maximum of three throws, then his expected gain/loss (in rupees) is:

Three balanced coins are tossed simultaneously. If denotes the number of heads, find the probability distribution of .

Product of the variance and standard deviation of the random variable X whose probability
distribution is given below

Let the p.m.f. of a random variable be and otherwise. Then value of is

If is a random variable with probability distribution then

If the mean and variance of a binomial variable are and respectively, find the parameter of the distribution . (Binomial).

A cubical die is thrown. Find the mean and variance of , giving the number on the face shows up.

The mean and variance of a binomial distribution are 4 and 3 respectively. Fix the distribution and find .

Following is the distribution function F (x) of a discrete r.v. X
Find

Let have p.m.f.
otherwise.
Find variance of .

The p.m.f. for number of major defects in a randomly selected appliance of a certain type is:
Find the standard deviation of .

A r.v. has the following probability distribution :
Find the value of and calculate mean and variance of .

The p.m.f. of a r.v. is
for
otherwise.
Find .

The probability distribution of a discrete random variable is
Determine the value of .

A random variable , has the probability distribution as given below. Let and then

Following is the distribution function of a discrete r.v.
Find the probability distribution of .

A random variable has the following probability distribution
Find .

Obtain the probability distribution of the number of sixes in two tosses of a fair die.

Determine such that the following function is a probability mass function.
