SOLUTION: A discrete random variable X has the probability mass function P(x) = 4x-x^2/a for x = 0, 1, 2, 3. What is the value of a? Ans: a=10. How do I solve this, please explain!

Algebra ->  Probability-and-statistics -> SOLUTION: A discrete random variable X has the probability mass function P(x) = 4x-x^2/a for x = 0, 1, 2, 3. What is the value of a? Ans: a=10. How do I solve this, please explain!      Log On


   

Question 1189200: A discrete random variable X has the probability mass function P(x) = 4x-x^2/a for x = 0, 1, 2, 3. What is the value of a?
Ans: a=10. How do I solve this, please explain!
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


I can tell you how to solve it; but I can't show you the solution because I don't know what the function is.

Is it 4x-x^2/a = 4x-x%5E2%2Fa?

Or is it (4x-x^2)/a = %284x-x%5E2%29%2Fa?

If your mathematical education is to the point where you are working on a problem like this, you should know by now that parentheses are important....

HOW to solve it is easy: the sum of all the probabilities must be 1: P(0)+P(1)+P(2)+P(3)=1

Whatever the function is, evaluate it for each value of x and solve that equation to find the value of a.