Real-Life Scenarios
Text Version

(Introduction music)
Image description: Khalid and Marissa are sitting at a table in a classroom.

Khalid:  Let’s think about the situation.  According to the data we collected, I have an 80% chance of answering each history question posed during the It’s Academic Tournament correctly.

Image description: Khalid points to the data table of his results and the equation, the probability of answering correctly equals 80% appears at the bottom of the data table.

Marissa:  Answering one of the history questions incorrectly does not impact your chances of answering any of the other history questions correctly during the tournament.

Khalid:  Right.  That means that answering each question represents independent events.  Now, that makes finding the probability easier.  If events are independent, then we simply have to multiply the probability for each event.

Image description: As Khalid speaks, the term “independent events” appears on the screen, followed by the probability of A times the probability of B.

Marissa:  Since the probability of answering all questions correctly is the product of answering each individual question correctly, we would multiply (0.8)(0.8)(0.8)(0.8)(0.8)(0.8)(0.8)(0.8), which means you have a 16.8% chance answering all 8 questions correctly.

Image description: As Marissa speaks a calculator screen shows her entering the numbers she describes.