SOLUTION: A box contains twenty-one doughnuts. Thirteen are filled with vanilla creme and eight are filled with lemon creme. Millicent randomly selects three doughnuts from the box. (The dou

Algebra ->  Probability-and-statistics -> SOLUTION: A box contains twenty-one doughnuts. Thirteen are filled with vanilla creme and eight are filled with lemon creme. Millicent randomly selects three doughnuts from the box. (The dou      Log On


   

Question 1185517: A box contains twenty-one doughnuts. Thirteen are filled with vanilla creme and eight are filled with lemon creme. Millicent randomly selects three doughnuts from the box. (The doughnuts all look the same.)
What is the probability that Millicent gets at least one doughnut that is filled with lemon creme?
Write your answer as a decimal, rounded to three significant figures.
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
21C3 possible choices
8C1*13C2 are ways for 1 lemon creme=624 ways
8C2*13C1 are for 2 =364 ways
8C3*13C0 are for three=56 ways
total 1044 ways/1330=0.785 probability
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also look at it for ways can choose 3 filled with vanilla creme and subtract that probability from 1, since everything else has at least 1 lemon creme.
13C3/21C3=0.2150
1-0.2150=0.785