Word Problems Guide – Probability – Ch 7 – #6 – Desserts

[carla.hales]

“John invites 12 people, half are men. Exactly one man and one woman are brining desserts. If 1 person from the group is selected at random, what is the probability that it is a woman or a man brining a dessert?”
I thought I understood the logic behind the answer, but previous answers to this question from your posts on 8/21/14 and 10/9/14 are contradictory (the first states the answer is 5/6, the second states the answer is 11/12).
I can understand why the answer would be 11/12 if the question stated, “If one person from the guests is selected at random…” But to fully answer this question, wouldn’t you consider John a part of the group? Therefore, P(woman) = 6/13 and P(man w/o dessert) = 6/13, after summing the answer would be 12/13.

[tommywallach]

Hey Carla,

John invites people to his party. So he's not bringing anything to his own party. (He might be SERVING something, but you wouldn't call it bringing.)

If we do have contradictory posts, though, please provide me with the links! (Also, in the future, you should just add your commentary to one of those posts, not a new one. I'll always see it.)

-t