Asked by Anonymous
urn contains 4 white and 6 red rolls. Four balls are drawn at random (without replacement) from the urn. Find the probability distribution of number of white balls?
Answers
Answered by
Reiny
prob(white) = 4/10 = 2/5, prob(red) = 6/10 = 3/5
no white balls --- (3/5)^4 = 81/625
one white ball -- C(4,1) (2/5) (3/5)^3 = 216/625
two white balls -- C(4,2) (2/5)^2 (3/5)^2 = 216/625
three white balls -- C(4,3) (2/5)^3 (3/5) = 96/625
four white balls -- (2/5)^4 = 16/625
notice that the sum of these is 1 , as it should be
no white balls --- (3/5)^4 = 81/625
one white ball -- C(4,1) (2/5) (3/5)^3 = 216/625
two white balls -- C(4,2) (2/5)^2 (3/5)^2 = 216/625
three white balls -- C(4,3) (2/5)^3 (3/5) = 96/625
four white balls -- (2/5)^4 = 16/625
notice that the sum of these is 1 , as it should be
There are no AI answers yet. The ability to request AI answers is coming soon!
Submit Your Answer
We prioritize human answers over AI answers.
If you are human, and you can answer this question, please submit your answer.