Question

Suppose 5 men and 7 women are on a crowded elevator. At the next floor, four people get off the elevator. Find the probability that two are women.

Answer 1

And find the probability that one is a woman.

Answer 2

to the one one, its 7/13

Answer 3

Thats not an answer for either

Answer 4

argh, havnt done this in 4 years, and im racking my brain:P gimmie a moment,

Answer 5

okay thanks, ive just been doing all sorts of stuff and i got nothing

Answer 6

This is sampling without replacement. Seems complicated. Might find the number of combinations of 12 things taken four at a time. Perhaps looking at those foursomes would be productive. I don't now.

Answer 7

if you meant exactly two women then
(7C2) (5C2) / (12C4) = 14/33

Answer 8

yea that was it i think

Answer 9

do you mind helping me with the "one woman" part also? @sourwing

Answer 10

one women means, 1W and 3M.

(7C1) (5C3) / (12C4) = 14/99

Answer 11

Thanks for explaining too i was not getting it, but i got it now! Thanx! @sourwing

Answer 12

@sourwing Very nicely done.