A California license plate starts with a digit other than 0 followed by three capital letters followed by three digits (0 through 9). How many different California license plates are possible?



Answer :

i will use a slot set up, and fill it in with the info given:
__   __   __   __   __   __   __

the first number can't be zero, this means there are 9 options for the first letter
for the 3 letters, there are 26 options for each letter
the last three numbers include 0, this means there are 10 options for each number
__   __   __   __   __   __   __
 9    26   26   26   10   10   10

to account for all the options, the options for each slot should be multiplied
 9 x 26 x 26 x 26 x 10 x 10 x 10 = 158,184,000 different licence plates possible