SOLUTION: You toss a fair 6-sided die 5 times.find the probability that a three is rolled exactly two out of the five rolls.

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Question 388089: You toss a fair 6-sided die 5 times.find the probability that a three is rolled exactly two out of the five rolls.
Found 2 solutions by ewatrrr, edjones:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
Note: The probability of x successes in n trials is:
P = nCx* p%5Ex%2Aq%5E%28n-x%29 where p and q are the probabilities of success and failure respectively. In this case p = 1/6 and q = 5/6
nCx = n%21%2F%28x%21%28n-x%21%29%29
P(2 successes out of five rolls) = 10(1/6)^2(5/6)^3 = .1608

Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
The probability that it is rolled on a single roll is 1/6
x=1/6 and y=5/6
(x+y)^5 We want the 4th term, x^2y^3
To find the coefficient use nCr=n!/((n-r)!*r!)=5C3=10
10x^2y^3=.16
.
Ed