SOLUTION: Question: Eileen has 4 cards, each with one of the following numbers printed on it: 9, 1,8,2 if she arranges a particular group of three cards in a line, how many possible arra

Algebra ->  Probability-and-statistics -> SOLUTION: Question: Eileen has 4 cards, each with one of the following numbers printed on it: 9, 1,8,2 if she arranges a particular group of three cards in a line, how many possible arra      Log On


   

Question 1184366: Question: Eileen has 4 cards, each with one of the following numbers printed on it: 9, 1,8,2
if she arranges a particular group of three cards in a line, how many possible arrangements are there?
Ans: 6. My answer: 4*3*2 = 24 Can someone please explain why I'm wrong?
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


It's a trick question, and therefore a bad one for a student who is just learning about permutations and combinations.

The key to getting the answer 6 is that the problem says she is arranging A PARTICULAR GROUP OF THREE CARDS in a line.

Therefore the three cards to be arranged have already been selected; and the number of ways of arranging them is 3*2*1=6.