Counting

Today we talked about counting things. We learned permutations and combinations. We also tried a few handshaking problems.

Homework

Find out how many paths are there from A to B. Note: you can only travel downward or to the right. You cannot go up or to the left.

A .____.____.____. | | | | | | | | .____.____.____. | | | | | | | | .____.____.____.____.____. | | | | | | | | | | | | .____.____.____.____.____. | | | | | | | | .____.____.____. | | | | | | | | .____.____.____. B