244,181 views
22 votes
22 votes
Nick buys a bag of cookies that contains 9 chocolate chip cookies, 6 peanut butter cookies, 7 sugar cookies and 7 oatmeal cookies. What is the probability that Nick randomly selects a sugar cookie from the bag, eats it, then randomly selects a chocolate chip cookie? Express you answer as a reduced fraction.

User Luca Manzo
by
2.9k points

2 Answers

6 votes
6 votes

Answer: 2/29

Step-by-step explanation: because he has 29 cookies in total therefor if he just randomly picks a cookie from the bag this would be 2/29 as he randomly chose 2 cookies out of 29 total cookie. we have no idea what he could have chose and all the cookies are mixed in a bag.

User Peter Zhou
by
2.6k points
9 votes
9 votes

Answer: 9/116

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Step-by-step explanation:

There are 7 sugar cookies

This is out of 9+6+7+7 = 29 total cookies

The probability of getting a sugar cookie is 7/29

After that cookie is selected, the total drops to 29-1 = 28 cookies. The probability of getting a chocolate chip on the second selection is 9/28

Multiply the fractions mentioned to get the final answer

(7/29)*(9/28) = (7*9)/(29*28) = (7*9)/(29*7*4) = 9/(29*4) = 9/116

User Peter Gerdes
by
3.1k points