Social Security Numbers A social security number consists of nine digits. How many different social security numbers are possible if repetition of digits is permitted?

Question

Is it 9^10??

Jen · Accepted Answer

Ms. Sue, wouldn't it be 9^10? I think 0 wasn't included, so it would be 10 numbers not 9.....right???

Ms. Sue · Answer

http://www.jiskha.com/display.cgi?id=1311437782

Ms. Sue · Answer

I'm not sure. Please post this as a New Question. That way a math tutor may be able to help you.

PsyDAG · Answer

For social security numbers, 0 can be included. n^r = 10^9, where n is the number of things to choose from, and you choose r of them (Repetition allowed, order matters)

Jen · Answer

so it would be 1,000,000,000???

Lady baby · Answer

But how about if repetition of digits are NOT allowed??