Page 100 - Probability Demystified

CHAPTER 5 Odds and Expectation 89

Summary

Odds are used to determine the payoffs in gambling games such as lotteries,
horse races, and sports betting. Odds are computed from probabilities; how-
ever, probabilities can be computed from odds if the true odds are known.
Mathematical expectation can be thought of more or less as a long run
average. If the game is played many times, the average of the outcomes or the
payouts can be computed using mathematical expectation.

CHAPTER QUIZ

1. Three coins are tossed. What are the odds in favor of getting 3 heads?
a. 1:7
b. 3:8
c. 7:1
d. 8:3
2. When two dice are rolled, what are the odds against getting doubles?

a. 1:5
b. 1:6
c. 5:1
d. 6:1
3. When a card is selected from a deck of 52 cards, what are the odds in
favor of getting a face card?
a. 5:2
b. 3:10
c. 12:1
d. 2:5
4. When a die is rolled, what are the odds in favor of getting a 5 or a 6?

a. 2:3
b. 1:2
c. 3:2
d. 2:1