Probability

Question

An urn contains white balls and red balls. If Juan chooses balls at random from the urn, what is the probability that he will select white balls and red balls? Round your answer to decimal places.

Answer 1

10w, 6r

13 chosen at random

P(9w, 4r) is ??

16 total

16C13(9/16)^9(6/16)^4

= 16!/13!3!(9^9)(6^4)/(16^9)(16^4)

= 16x15x14/3x2)(9^9)(6^4)(16^13)

= 8x5x14x9^9)(36^2)/16^13)

= 560x9^9)(1296)/4.503599626x10^15

= 2.811742941x10^14/4.50359962626x10^15

= .2811742941/4.50359962626

= 0.062433235

P(exactly 9 white & 4 red) = about 6.243%