Can you answer this Riddle?
You're going to a friends house and want to give them some brownies. On the way to their house you cross 5 bridges. At each bridge you must pay a toll of half of your brownies to the owner. But they are all very nice and give you back a brownie from what you give them. How many brownies must you start with to give your friend 2 brownies?



You must start with 2 brownies. 

At each toll bridge, you give the half of brownies you have, i.e. 1 brownie. However,since the owners give back one brownie and have received only 1 brownie, they ought to return it.

This way, you give 1 brownie to each owner, he returns it back to you and you finally gift 2 brownies to your friend.