Question

A 6 character computer password is made up of 4 numbers followed by 2 letters. How many different passwords are possible?
a.
810,000
b.
3,276,000
c.
6,500,000
d.
6,760,000

Answer 1

For each of the 4 number positions there are 10 choices (0–9), and for each of the 2 letter positions there are 26 choices.
Total = 10^4 × 26^2 = 10,000 × 676 = 6,760,000.

Answer: d.