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Alice and Bob each choose at random a number between zero and two. We assume a uniform probability law under which the probability of an event is proportional to its area. Consider the following events:

A: The magnitude of the difference of the two numbers is greater than 1/3.
B: At least one of the numbers is greater than 1/3.
C: The two numbers are equa
D: Alice's number is greater than 1/3.

User MaxPi
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1 Answer

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Final answer:

To find the probabilities of the events A, B, C, and D in Alice and Bob's random number selection, we consider the possible outcomes and calculate the probabilities. P(A) = 2/9, P(B) = 7/9, P(C) = 1/3, and P(D) = 2/3.

Step-by-step explanation:

To find the probabilities of the events A, B, C, and D, we need to understand the concepts of probability and independent events. In this case, Alice and Bob each choose a number between zero and two, so there are a total of 3 x 3 = 9 possible outcomes. Let's calculate the probabilities for each event:

A: The magnitude of the difference of the two numbers is greater than 1/3. There are two possible outcomes where this event occurs: (0, 2) and (2, 0). Therefore, P(A) = 2/9.

B: At least one of the numbers is greater than 1/3. There are seven possible outcomes where this event occurs: (1, 0), (2, 0), (0, 1), (0, 2), (1, 1), (1, 2), (2, 1). Therefore, P(B) = 7/9.

C: The two numbers are equal. There are three possible outcomes where this event occurs: (0, 0), (1, 1), (2, 2). Therefore, P(C) = 3/9 = 1/3.

D: Alice's number is greater than 1/3. There are six possible outcomes where this event occurs: (1, 0), (2, 0), (1, 1), (1, 2), (2, 1), (2, 2). Therefore, P(D) = 6/9 = 2/3.

User Raghav RV
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