Expert: Josh - 2/27/2009

Question
what is the formula (simplified for  7th grade) for finding the probability of
drawing 3 queens from a deck of cards?

Answer
Hi Tom,

We start with 4 queens in a full deck of cards. For the first pick, there is a 4 out of 52 chance of drawing a queen.

Now, if one of the queens is removed, we will be left with 3 queens out of 51 cards. So, the chance of drawing a queen the second time is 3 out of 51.

If this happens, we will be left with 2 queens in the 50 cards remaining. So, the chance of drawing a queen for the third consecutive time is 2 out of 50.

To get this series of events happening, we multiply the individual probabilities to get the final answer: (4/52)x(3/51)x(2/50). You can simplify this expression if you like, and multiply the number by 100 to get a percentage.