Question 462478:  Hi, I have already sumitted this problem once, but havent gotten a reply, can someone help me? 
a mini license plate for a toy car must consist of a number followed by two letters.  Each letter must be a C, A, or R.  each number must be a 3 or 7. repetition of letters is permitted. 
.use the counting principle to determine the number of points in the sample space. 
.construct a tree diagram to represent this situation. 
.list the sample space. 
.determine the exact probability of creating a mini license plate with a C. give solutions exactly in reduced fraction form. 
 Answer by edjones(8007)      (Show Source): 
You can  put this solution on YOUR website! Since "a mini license plate for a toy car MUST consist of a number followed by two letters" then the following are the only arrangements allowed for the letters: 
CC, CA, CR, AC, RC, AA, AR, RA, RR The sample space. 
There are 5 containing a C out of 9. 
5/9  the exact probability of creating a mini license plate with a C. 
. 
Ed 
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