You take a three-question true or false quiz. You guess on all the questions. What is the probability that you will get a perfect score?

For each question, there are two options: True or False. Thus, if you guess on all of the questions, there is a 1/2 chance that you get the answer right.

If there are three questions on the test, the chance that you get a perfect score is:

1/2 * 1/2 * 1/2

When this is simplified, you get:

1/4 * 1/2

OR:

1/8

Therefore, the probability that you will get a perfect score is 1/8 or 12.5%