SOLUTION: Gianna buys a bag of cookies that contains 5 chocolate chip cookies, 9 peanut butter cookies, 4 sugar cookies and 6 oatmeal cookies. What is the probability that Gianna reaches

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Question 1200401: Gianna buys a bag of cookies that contains 5 chocolate chip cookies, 9 peanut butter cookies, 4 sugar cookies and 6 oatmeal cookies.
What is the probability that Gianna reaches in the bag and randomly selects 2 sugar cookies from the bag? Round your answer to four decimal places.
Found 2 solutions by Solver92311, greenestamps:
Answer by Solver92311(821) (Show Source):
You can put this solution on YOUR website!

There are 24 cookies in the bag. The probability that the first of two cookies selected is a sugar cookie of which there are 4 is 4 divided by 24. Given that the first selection is a sugar cookie, then there are 23 total cookies left in the bag of which 3 are sugar cookies, probability . Since the first and second draws are independent events, the total probability is the product of the two independent probabilities:

You can do your own arithmetic.

John

My calculator said it, I believe it, that settles it

From
I > Ø

Answer by greenestamps(13198) (Show Source):
You can put this solution on YOUR website!

The response from the other tutor shows one basic way to calculate this probability -- by looking at the probability that the first cookie is a sugar cookie and then the next one is also.

You should know the other basic method for computing this kind of probability, as follows.

The number of ways of choosing 2 of the 24 cookies is C(24,2) = "24 choose 2"; the number of ways of choosing 2 sugar cookies is C(4,2) = "4 choose 2". The probability of getting 2 sugar cookies is then