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1. An experiment consists of three steps. There are five possible results on the first step, two possible results on the second step, and four possible results on the third step. What is the total number of experimental outcomes?

2. Six names are put in a hat. Two names are selected at random from the hat. How many different selections are possible?

3 The "Quinella" at a racetrack consists of picking the correct order of the first two horses in a race. If there are 7 horses in a particular race, how many "Quinella" outcomes are possible?

4. A combination lock has four dials (see the picture below). Each dial has the numbers 0 through 9.

5. Let a sample space be S = {E1, E2, E3, E4, E5} with the following probabilities:

P(E1) = 0.2, P(E2) = 0.1 P(E3) = 0.4 P(E4) = 0.1

a. Find P(E5).

b. If event A = {E1, E2}, find P(A).

c. If event B = {E2, E3, E4}, list the sample points in event BC.

d. Are event A = {E1, E2} and event C = {E3, E4, E5} mutually exclusive. Explain.

The sales records of a real estate agency show the following sales over the past 200 days

Number of	Number
Houses Sold	of Days
0	60
1	80
2	40
3	16
4	4

What is the probability of selling 3 or more houses?

6 Of the last 40 customers entering a convenience store, 5 have purchased a lottery ticket. a. If the relative frequency method for computing probability is used, what is the probability that the next customer will purchase a lottery ticket? b. If the classical method for computing probability is used, what is the probability that the next customer will purchase a lottery ticket?

a. How many different combinations are possible?

b. If no two dials can have the same number, how many combinations are possible?

7 Given P(A)  0.38, P(B)  0.83, and P(A ∩ B)  0.57; find P(A U B)

 The travel time for a college student traveling between her home and her college is uniformly distributed between 40 and 90 minutes. a. Find the value of the probability density function, f(x). b. What is the probability that her travel time will be between 40 and 80 minutes? c. What is the probability that her travel time will not be greater than 60 minutes? d. What is the probability that her travel time will be between 20 and 30 minutes?

9. Z is a standard normal random variable. Compute the following probabilities.

a.	P(z ≤
b.	P(z ≤
c.	P(-1.23 ≤ z ≤ 2.58)
d.	P(z ≥ 1.32)

10. Z is a standard normal random variable. Find the following z values. a. What is the value of z if the area to the left of z is 0.9515? b. What is the value of z if the area to the left of z is 0.1249? c. What is the value of z if the area to the right of z is 0.33?