Let X be a continuous random variable on the interval [-1, 1] with pdf p(x) = 1 - |x|

- you could think of this as the "poor man's bell-shaped curve".

(a) What is P(0 < X < 1)?

(b)What is P(-1/2 < X < 1/2)?

c) What is E(X)? What is V(x)?

Let Y be a random variable that is exponentially distributed with E(Y)= 25.

(a) What is the pdf of Y?

(b) What is the variance of Y ?

(c) Suppose Y models how long you have to wait for something. And suppose you have already waited for 15 minutes? How much longer do you expect to have to wait?