In the preceding section, we learned about complementary events. In this section, we will continue to examine the relationship between two events.

In this section, we will use a trial of drawing one ball out of a container.

Description of the trial: We assume that we have a container with 5 balls.

We put our hand into the container (with our eyes covered), and draw one ball out randomly.

Through this trial, we will illustrate the terms and calculations in this section.