Brainteaser: A bat and a ball cost $1.10 together. The bat costs $1.00 more than the ball. How much does the ball cost?
Answer: Five cents. Most people say ten, but check it: if the ball were 10 cents, the bat would be $1.10, and together they’d come to $1.20. Here’s the working. Call the ball x. The bat is x plus $1.00. So x + (x + $1.00) = $1.10, which means 2x = $0.10, so x = $0.05. The ball is 5 cents and the bat is $1.05, and $1.05 is exactly a dollar more than 5 cents.
