Algebra and Trigonometry, 5th Edition

11.8 Probability

• Compute the probability of a simple event.

When a coin is tossed, we can reason that the chance, or the likelihood, that it will fall heads is 1 out of 2—that is, the probability that it will fall heads is $\frac{1}{2}$. Of course, this does not mean that if a coin is tossed 10 times it will necessarily fall heads 5 times. If the coin is a “fair coin” and it is tossed a great many times, however, it will fall heads very nearly half of the time. Here we give an introduction to two kinds of probability, experimental and theoretical.

Experimental Probability and Theoretical Probability

If we toss a coin a great number of times—say, 1000—and count the number of times it falls heads, we can determine the probability that it will fall heads. ...