Logic Riddles

Question: You are in a car with some helium balloons and hit the gas. While you accelerate, which way does the balloon move?

Question: 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?

Question: Two men, Watson and Holmes, are out in the extremely dry forest. They are completely surrounded by a large forest fire on one side and a dangerous cliff on the other. The wind is blowing the forest fire towards them and the cliff. The fire will reach them in about one day.

Holmes turns to Watson, "I have matches, berries, and enough water for a day. We aren't going to die." How can they avoid getting swallowed up by the forest fire?

Question: You have a flashlight that takes 2 working batteries. You have 8 batteries but only 4 of them work.

What is the fewest number of pairs you need to test to guarantee you can get the flashlight on?

Question: A cheap man and his wife decide to go on a trip for their 10th anniversary. They go to Brazil and while touring the rain forest his wife falls off of a bridge to her death.

Shortly after her death one of the flight attendants on their flight sees a report on her death on television. She immediately calls the police and tells them the man murdered his wife.

How did she know?