SOLUTION: Four marbles are drawn from a bag containing six green and five purple marbles. What is the probability that all four marbles are purple? i) if the marble is replaced after eac

Algebra ->  Probability-and-statistics -> SOLUTION: Four marbles are drawn from a bag containing six green and five purple marbles. What is the probability that all four marbles are purple? i) if the marble is replaced after eac      Log On


   

Question 1168514: Four marbles are drawn from a bag containing six green and five purple marbles.
What is the probability that all four marbles are purple?
i) if the marble is replaced after each draw?
ii) if the marbles are not replaced?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
if replaced, it is (5/11)^4=0.04269
if not replaced, it is (5/11)(4/10)(3/9)(2/8)=120/7920=0.01515 (repeat)
also
11C4 are the number of outcomes, or 330
5C4 are the ways to choose 4 purple marbles =5
it is 5/330 or 1/66 in this scenario. That is 0.01515...