MATH Prob.
posted by Twg on .
How many threesymbol codes can be formed from the
letters I, S, P, and Y without repetition?

What is 4*3*2?

Can you please show me how you got that answer?

How many threesymbol codes (letternumbernumber)
can be made from the letters S, P, Y, and two digits
from the set {0, 1, 2,....., 9} without repetition? 
As far as your first question, I think bobpursley is referring to 4! called "four factorial."