SOLUTION: I've been stuck on this question on my study guide and i really need to understand how to do it
An urn contains 4 white balls and 3 green balls. A set of 3 balls are drawn from
Algebra ->
Probability-and-statistics
-> SOLUTION: I've been stuck on this question on my study guide and i really need to understand how to do it
An urn contains 4 white balls and 3 green balls. A set of 3 balls are drawn from
Log On
Question 946484: I've been stuck on this question on my study guide and i really need to understand how to do it
An urn contains 4 white balls and 3 green balls. A set of 3 balls are drawn from the urn. Find the probability that the third ball is white given that the first two are white. Answer by Theo(13342) (Show Source):
the probability of drawing a white ball on the first draw is therefore 4/7.
your first draw is a white ball.
there are 3 white balls out of 6 left in the urn after the first draw.
the probability of drawing a white ball on the second draw is therefore 3/6.
your second draw is a white ball.
there are 2 white balls out of 5 left in the urn after the second draw.
the probability of drawing a white ball on the third draw is therefore 2/5.
given that you drew a white ball on the first 2 draws, the probability of drawing a white ball on the third draw is 2/5 because there are 2 white balls left out of a total of 5 balls left in the urn.
