math157
posted by Tami on .
How many threesymbol codes (letternumbernumber) can be made from the letters S, P, Y and two digits from the set {0, 1, 2, …,9} without repetition?
I think I am suppose to match each letter with a number until I exhaust all possibilities but I am not sure can you help please?

for the letter: determine first how many letters are possible,,
there are 3 *S, P, Y
for the first number: how many are possible,,
there are 10 *0,1,2,..9
for the second number: since no repetition is allowed, there only 9 possible,,,
then multiply:
3*10*9 = 270 possibilities
so there,, =) 
Wonderful, Thanks for your hel:)