Question: The following table provides a probability distribution for the random variable x.

X f(x)

20 .20

25 .15

30 .25

35 .40

a) What is the probability that X = 28

b) What is the probability that X = 30

c) What is the probability that X is less than or equal to 25.

d) What is the expected value of X? Compute the variance of X and the standard deviation of X.

e) Is this a discrete or random variable or a continuous random variable? Why?