Answer:
There are many colored pebbles to choose from out of the driveway. Karmin could not decide what one he wanted for his school project. So he took the best looking 4 from the driveway. 3 of them are now his backups.
You use this tequnic (sorry I can't spell) almost everyday. When ever you think about how much of something to take, you could be using this Pascal Triangle.
I hope this helped.
