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 solution exactly in reduced fraction form

Question

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 solution exactly in reduced fraction form

anonymous · Answer

please help

y2o2 · Answer

So, the number must be in this for (N L1 L2) , where N is numbers and L is letters.
A)
according to the counting principle ; the number of N = 2
and the number L1  = L2 = 3  (since repetition is permitted)

so the  number of points in the sample space =  2 * 3 * 3 = 18

the number of points with "C" = 2 *1 *3 = 6

so the probability of a plate with "C" is (6/18) = (1/3)

anonymous · Answer

how do u construct a tree diagram to represet this

y2o2 · Answer

actually I can't draw it here