PROBABILITY ASSIGNMENT
1. Multiple Choice Tests A multiple choice test contains four answer choices (A, B, C, and D) for each question. You guess randomly on two questions on the test.
a. Make a tree diagram of the possible answers for the two questions.
b. What is the probability that you answer both questions correctly?
c. Analyze Suppose the answer to both questions is A. Use the tree diagram to count how many outcomes there are in which you answer at least one of the two questions correctly. What is the probability that you answer at least one question correctly?
2. Challenge You roll an 8-sided number octahedron, and your friend rolls a 4-sided number pyramid.
a. How many different possible outcomes are there for the pairs of numbers rolled?
b. Find the probability that you and your friend roll the same number.
c. Find the odds in favor of rolling a number greater than the number your friend rolls.
3. Phone Numbers You remember part of your friend’s 7-digit phone number, but you cannot remember the rest.
a. Your friend’s number begins with 79 and ends with five other digits. How many different phone numbers can begin with 79?
b. You remember that the next digit after 79 is 8. How many possible phone numbers can begin with 798?
c. How many digits of a 7-digit phone number do you have to know before the probability that you randomly guess the number . correctly on the first t 1/100?
