points in order for the bettor to win. If
Army wins by exactly five points, the
game is called a “push,” and no one wins.
How does a person determine the
oddsin horse racing?
The track makes its money in a certain
mathematical way: When the odds of the
horse race are converted to probabilities,
they usually add up to more than 1, giv-
ing the track the advantage. For example,
say a race track has 12 races with four
horses, and the odds of winning each race
are as follows (note: race tracks don’t use
the same horse in each race—this exam-
ple is for illustrative purposes only):
- Horse 1—1:1; probability
chances for (1) / total chances (1- 1/2 or 6/12
- Horse 2—2:1; 1 / (1 2) 1/3 or
4/12 - Horse 3—3:1; 1 / (1 3) 1/4 or 3/12
- Horse 4—5:1; 1 / (1 5) 1/6 or 2/12
If a person puts $1 bets on horse number 2, he or she would have to win 4 out of
12 races to break even. But note: All these numbers add up to 15/12, or 1.25, a higher
number than 1, so as long as no horse wins more than its probability, the house wins.
There’s another way of looking at this type of betting. In order for the gambler to
do “better” than the track, he or she has to win 15 times in 12 races—a physical and
mathematical impossibility—which is why the track always makes money. Of course,
a gambler may bet on certain low-probability horses that win more races than expect-
ed, earning a few more dollars along the way, but don’t bet on it.
JUST FOR FUN
What is number guessing?
Number guessing is a game (some say trick). Some people can do number guessing in
their heads, as long as the numbers are kept small. Have a person think of any positive
integer n(not zero or any negative numbers) and apply the following steps: 437
RECREATIONAL MATH
Numbers are used to identify cars with VIN num-
bers, and to help people figure out which car con-
tains their favorite driver in a NASCAR race. The
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