Monopoly Game Example

Mutually Exclusive

• Problem:• Laura is playing Monopoly. On her next move

she needs to throw a sum bigger than 8 on the two dice in order to land on her own property and pass GO.

• What is the probability that Laura will roll a sum bigger than 8?

• Solution:• The only sums larger than 8 are 9, 10, 11, and

12• The outcomes are MUTUALLY EXCLUSIVE• P(9 or 10 or 11 or 12)• P(9) + (10) + (11) + (12) =

• How can we get a 9 on two dice? Die 1 Die 2 3 6 6 3 4 5 5 4Since there are 36 total outcomes and there are 4

ways to get a 9, the probability of getting a 9 on two dice is 4/36

• Compute the probabilities for 10, 11, and 12 the same way

P(10) = 3/36P(11) = 2/36P(12) = 1/36

• Since the outcomes are mutually exclusive, ADD the probabilities

• P(9) + P(10) + P(11) + P(12) = 4/36 + 3/36 + 2/36 + 1/36 = 10/36 = 5/18