Solve the below problem:
Q: Three tables listed below show "random variables" and their "probabilities." However, only one of these is actually a probability distribution.
a. Which is it?
x P(x) x P(x) x P(x)
5 .3 5 .1 5 .5
10 .3 10 .3 10 .3
15 .2 15 2 15 -2
20 .4 20 .4 20 .4
b. Using the correct probability distribution, find the probability that x is:
(1) Exactly 15.
(2) No more than 10.
(3) More than 5.
c. Compute the mean, variance, and standard deviation of this distribution.