Internet Exercises

Here's a fun exercise demonstrating probability based on the popular, 70s television game show, Let's Make A Deal. In the show, a contestant chose from one of three doors containing a prize. Two of the doors contained gag gifts; one door contained a true prize. After a contestant chose an initial door, the game show host revealed one of the unchosen doors and gave the contestant an opportunity to change his/her selection. Does the probability of winning change and get better if the contestant switches doors? Try the "Let's Make a Deal Applet" and keep track of wins and loses. The ultimate question is, what is the probability of winning if a contestant switches doors compared to not switching doors?

Try this applet to see if you can figure the probability of two people having the same birthday in a room of people, with the number of people varying. First select "generate 15" birthdays and click the start button. In the lower right corner look to see if there are any matching birthdays. Keep track of these by the size of the n. Then select restart and select "generate 20" birthdays and click start. Repeat this until you get at least one birthday match. What was the size of n? Afterwards, experiment with different size n. Reset the applet and select "generate 100" birthdays and see how many randomly generated birthdays are matches.