2007 AMC 8 Problems/Problem 21
Problem
Two cards are dealt from a deck of four red cards labeled ,
,
,
and four green cards labeled
,
,
,
. A winning pair is two of the same color or two of the same letter. What is the probability of drawing a winning pair?
Solution
There are 4 ways of choosing a winning pair of the same number, and ways to choose a pair of the same color.
There's a total of ways to choose a pair, so the probability is
.