Question

Karissa buys a bag of cookies that contains 4 chocolate chip cookies, 4 peanut butter cookies, 9 sugar cookies and 6 oatmeal cookies. What is the probability that Karissa reaches in the bag and randomly selects an oatmeal cookie from the bag, eats it, then reaches back in the bag and randomly selects a chocolate chip cookie

Answer 1

12 / 253

Explanation:

There are a total of 4 + 4 + 9 + 6 = 23 cookies in the bag, therefore, there are 23 * 22 = 506 ways to pick one cookie, eat it, and then pick another cookie. There are 6 ways to choose the first cookie (because there are 6 oatmeal cookies) and 4 ways to choose the second cookie (because there are 4 chocolate chip cookies) so there are 6 * 4 = 24 successful ways. The probability is thus 24 / 506 = 12 / 253.