Math Help Please?

Science & Mathematics by Anonymous 2018-07-06 23:33:55

Social Science

Math Help Please?

5 answers

An urn contains 1 red and 2 blue balls. Balls are drawn from the urn successively, at random and with replacement. What's the probability that exactly 3 blues occur in the first 5 trials?

Anonymous

For five trials: 2/3*2/3*2/3*1/3*1/3 = 8/243
Anonymous

10*(2/3)^3(1/3)^2 = 80/243
Anonymous

n=5 r=3 p=2/3 = 0.6667 P = 5C3*0.6667^3*0.3333^2 = 0.3292
Anonymous

X~Bi(n=5,p=2/3 Pr(X=3) = ... plug in formula of Binomial
Anonymous

With replacement, each draw has a 2 in 3 chance of drawing a blue. The odds for five trials are: (2/3)(2/3)(2/3)(2/3)(2/3) or 32/243