Take the Mensa challenge! These extraordinarily entertaining puzzles can confound even those with high IQs-and that's what makes them such delightfully tricky fun. A few can be solved relatively quickly, but the hardest may seem nearly impossible to crack. Give your skills a real workout on numerical conundrums, word games, lateral thinking problems, and riddles. Brainteasers, arranged in order of difficulty, train the mind and provide a good time all at once. The most complex bafflers include chess, logic, and spatial puzzles. Here's a small sampler of what's inside!� A farmer has twenty sheep, ten pigs, and ten cows. If we call the pigs cows, how many cows will he have?� Which three boys' names are anagrams of one another?Answers:1. Ten cows. We can call the pigs cows, but that doesn't make them cows.2. Arnold, Roland, and Ronald.