math
posted by Joyce on .
a liscence plate for a car must consist of a letter followed by two numbers. Each letter mus be an R, U or N. Each number must be a 2 or 6. Repetition of digits is permitted.
Use the counting principle to determine the number of points in the sample.
Construct a tree diagram.
List the sample space.
Determine the exact probability of creating a plate with an R. Give solution exactly in reduced fraction form.

1 letter from{R,U,N}  3 choices
1 digit from {2,6}  2 choices
1 digit from {2,6}  2 choices (repetitions allowed)
Total distinct licence plates, by the mulitiplication principle.
= 3*2*2 = 12