Originally Posted by

**wheresthecake** hey guys, need some help with this problem. this is one of four permutation problems that our teacher gave us to solve but haven't really figured it out, plus i was sick so i missed the lecture..

4) 3 balls are to be drawn one at a time from an urn containing 8 distinct ones. Find the number of ways these 3 balls can be drawn if a) a drawn ball has to be replaced before drawing the next and b) there is no replacement of drawn balls.

thanks for the help. we've been given all the basic formula for permutations but I'm at a loss at how to apply them still.