An unbiased die is tossed 3 times, suppose that a variable x is assigned the value k, when k consecutive sixes are obtained for else x takes the value –1 . Then expected value of x is:

An unbiased coin is tossed 5 times. Suppose that a variable X is assigned the value k when k consecutive heads are obtained for k=3,4,5 otherwise X takes the value -1 .Then the expected value of X ,is :

2 dice are thrown. Suppose a random variable X is assigned a value 2k, if the sum on the dice is equal to k, then the expected value of X is

2 dice are thrown. Suppose a random variable X is assigned a value 2k, if the sum on the dice is equal to k, then the expected value of X is

An unbaised coin is thrown 5 times. Let X be a random variable and k be the value of assigned to X for k=3,4,5 times Head occurs consecutively and otherwise the value of X is assigned -1. What is value of expection.

If x and y are random variables having expected values as 4.5 and 2.5 respectively, then the expected value of (x-y) is

Let X be the random variable of the number of points obtained in single throw of an unbiased die. Then, the value of barX is -

An unbiased coin is tossed 'n' xx.Let the randon variable X denote the number of xx the head occurs.If P(X=1),P(X=2) and P(X=3) are in AP, find the value of n .

If x+1 is a factor of x^3+k , then write the value of k.

A random variable X has the following probability distribution : Then, the expected value of X is