Posted by **matt** on Sunday, April 13, 2008 at 8:45pm.

Your password for a given website is made up of three letters followed by

four numbers. Find the number of possible passwords if there are no

restrictions on what three letters and what four numbers can be used.

- maths permutation and combination - answer pls check -
**matt**, Sunday, April 13, 2008 at 9:06pm
Pls check if my answer is correct

26C3*10C4

=26!/(26-3)!3! . 10!/(10-4)!4!

= 26*25*24*23!/23!*6 . 10*9*8*7*6!/6!*4*3*2*1

=15600/6 * 5040/24

=2600*210

=546000

- maths permutation and combination -
**bobpursley**, Sunday, April 13, 2008 at 9:38pm
I didn't see that letters or numbers cant be used more than once.

26*26*26*26*10*10*10*10

As I read it AAAA0000 is allowed, your number didn't include those.

- maths permutation and combination -
**matt**, Sunday, April 13, 2008 at 9:44pm
Thanks

## Answer this Question

## Related Questions

- maths permutation & combination - answer pls check - Your password for a given ...
- Permutations - A valid password on a Web site contains 3 letters (A-Z, 26 total...
- Permutations - A valid password on a Web site contains 3 letters (A-Z, 26 total...
- Integrated Math 1 - A valid password on a Web site contains 3 letters (A-Z, 26 ...
- Algebra - A password consists of three digits, 0 through 9, followed by three ...
- Probability(math) - How many computer passwords can be created with three digits...
- math - teresa has to create a password that contains 1 digit and 2 letters. find...
- Math - A password consists of 2 letters and 2 digits (0-9). The letters and ...
- math - a book club assigns to each member a membership number that consists of 2...
- Algebra - 42. Which number best represents this set of data: 5, 5, 5, 6, 5, 5, 5...

More Related Questions