8 – Cassie does not like to say her age. When someone asks, her mother answers for her. Cassie's mother says, "I'm seven times as old as Cassie now. In 20 years, Cassie will be half the age that I will be then." How old is Cassie now?

Answer

9 – Make this equation correct without changing the numbers: 8 + 8 = 91

Answer

Think a Little Harder...

10 – In your cellar, there are three light switches in the ‘off' position. Each switch controls one of three light bulbs on the floor above it. You may move any one of the switches but you may only go upstairs to inspect the bulbs once. How can you determine the switch for each bulb with only one inspection?

Answer

Looking for More?

Think of these sites as virtual gyms for your mind:

Brain Teasers and Math Puzzles
http://www.syvum.com/teasers

BrainBashers
http://www.brainbashers.com

Braingle
http://www.braingle.com

Bill's Games–Brain Teasers
http://www.billsgames.com/brain-teasers

For kids:

Brainteasers, Puzzles, & Riddles
http://www.niehs.nih.gov/kids/braint.htm

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