You can
put this solution on YOUR website! Suppose a license plate contains three letters followed by
three digits and the first digit cannot be zero. How many
different license plate can be printed?
[Notice that some of the 3 letters can be the same,
and some of the digits can be the same.]
Choose the letter to come first 26 ways.
Choose the letter to come second 26 ways. <-- 26, not 25 (can be the same)
Choose the letter to come third 26 ways.
Choose the digit to come fourth 9 ways. <-- Can't be zero!
Choose the digit to come fifth 10 ways. <-- Can be zero!
Choose the digit to come sixth 10 ways. <-- Can be zero!
26*26*26*9*10*10 = 15,818,400.
Edwin