Discrete Probability - Need Help Please!

Question

Suppose an experiment has seven possible outcomes for x: 0, 1, 2, 3, 4, 5, 6. The probability that each of these outcomes occurs is x/21. What is the expected value of x for the experiment?

Answer 1

Hi Jacob,

According to Wikipedia,

"More practically, the expected value of a discrete random variable is the probability-weighted average of all possible values. In other words, each possible value the random variable can assume is multiplied by its probability of occurring, and the resulting products are summed to produce the expected value."

 

Based on that statement, the expected value is the sum of the following products:

(0*0/21) + (1*1/21) + (2*2/21) + (3*3/21) + (4*4/21) + (5*5/21) + (6*6/21)

I will leave the final calculation to you.