Problema Solution

Serial numbers for a product are to be made using

3

letters followed by

3

numbers. If the letters are to be taken from the first

8

letters of the alphabet with no repeats and the numbers are taken from the digits

0

through

9

with repeats possible, how many serial numbers can be generated?

Answer provided by our tutors

The number of 3 letter combinations without repeating out of a set of 8 element (8 letters) is:

C(8, 3) = 8!/(3!(8 - 3)!)

C(8, 3) = 6*7*8/6

C(8, 3) = 56

The number of 3 digits combinations with repeating out of a set of 10 elements (10 letters) is:

P(10, 3) = 10^3

The total number of serial numbers generated is: 

56*10^3 = 56,000