### Home > CCG > Chapter 1 > Lesson 1.2.1 > Problem 1-55

Probability is used to make predictions. See the Math Notes in this lesson for more details. Whenever the outcomes are *equally likely*, the probability in general is:

For example, if you were to reach into a bag with

The example above shows all forms of writing probability:

Use the P(success) formula above to solve parts (a-d).

The historic carousel at the park has

giraffes, lions, elephants, horses, monkey, unicorns, ostriches, zebras, gazelles, and even dinosaur. Eric’s niece wants for Eric to randomly pick an animal to ride. What is the probability (expressed as a percent) that Eric picks a horse, a unicorn, or a zebra? Eduardo has in his pocket $1 in pennies, $1 in nickels, and $1 in dimes. If he randomly pulls out just one coin, what is the probability that he will pull out a dime?

with one regular die if you roll the die just once. P(dart hitting a shaded region) if the dart is randomly thrown and hits the target at right.