Scott can travel from Rochester, N.Y., to New York City by bus, train, car, or airplane. He can travel from New York to London, England, by airplane or ship.

Question

1. If Scott must return from London to New York by airplane, and from New York to Rochester by airplane, how many ways may he make the round trip?

Answer 1

Hmm. Looks like once he gets to London, there's only one way back. So, how many ways can he get to London?

4*2 = 8

Now, if we count the two legs by plane as a single "way", then he can get there

3*2 + 1 = 7