A security code contains 10 digits. The first 3 come from the letters {A,B,C,D,E,F,G,H,M,P,Q} Letters may repeat once used. The last 7 come from the numbers {0,1,. . .9}. Numbers may NOT repeat once used. How many security codes are possible?

any help would be appreciated. thank you

Apr 28th 2010, 02:11 PM

superpowerspacemonkey

804988800

Apr 28th 2010, 02:22 PM

drewbear

work needed!!!

can you please explain how you got that for an answer?

Apr 28th 2010, 03:44 PM

atalay

First 3 come from letters 26x26x26... (letters may repeated)

The last 7 come from, first 10 numbers (0,1,...,9) and second 9, third 8 etc. because numbers may not repeated.