Math Word Problem Challenge

My good friend Paige Eshelman sent this to me and it was a fun distraction, so I thought that I would share it with all of you. I challenge each of you to solve the problem below - post your answer as a comment. I got it right on the first try -- it took Doug three times. :)

Without further ado, here is the math word problem:

This is not a trick question. This is a real math problem so don't say that a bus has no legs.

There are 7 girls in a bus

Each girl has 7 backpacks

In each backpack, there are 7 big cats

For every big cat there are 7 little cats

Question: How many legs are there in the bus?


Don't disappoint me folks!