# Find a formula for p(x) = P(X=x)

1. ### sbarb25

2
Find a formula for p(x) = P(X=x) ....

So I have a test tomorrow and this question is in a list of review questions and I'm having trouble remembering where the mu fits into the formula. Any help would be greatly appreciated :)

Question: Suppose that X is a random variable with just two possible values a and b. For x = a and b find a formula for p(x) = P(X = x) in terms of a, b and mu = E(X).

2. ### Office_Shredder

4,487
Staff Emeritus
Re: Find a formula for p(x) = P(X=x) ....

If P(X=a)=p and P(X=b)=1-p, what can you say about E(X)?