Math Probability Question

[Trumpetman]

I need some help for all the math guros out there. How many four letter combinations can I get with 8 letters. Any of the 8 letters can be repeated as many times as you wish. It could be AAAA, AAAB, AABB, ABCD....etc. assuming you'd use the letters A-H. Thanks guys

 

[Interpol]

This is selection with replacement, and you have 8 characters to fill 4 slots, so:

8 * 8 * 8 * 8 = 4096

 

[DrMetallica]

without replacement, order doesn't matter, it's just 8 choose 4, do that on a calculator.

70.