Augustus loves candy and much to his delight, his three favorites are on sale. One each of gum, chocolate and caramel cost 40 cents. A caramel is over three times the price of gum. Six gums are worth more than chocolate. A caramel plus two gums cost less than chocolate. What is the price of each candy?
A red-house is made of red bricks, has a red wooden door and a red roof. A yellow-house is made of yellow bricks, has a yellow wooden door and a yellow roof. What is a green-house made of?
The problem works out to a set of three equations: b + c + d = 22 a + c + e = 22 a + b + c + d + e = 30
Solving for c = 14, leaving d = 8 – b and e = 8 – a. In other words, c must be 14, but the other two numbers just have to add up to 8. The requirement that they be unique rules out 4 + 4, so you’re left to choose from the following combations for b + d and a + e: 0 + 8 1 + 7 2 + 6 3 + 5
Franklin. It’s a list of the men on U.S. currency, $1, $2, $5, $10, $20 and $50. The $100 bill has Franklin. And an interesting tidbit is that Hamilton, along with Franklin, are the only two men in the list who did not serve as president.
A man owed his friend $63 and repaid him the exact amount in cash without using coins or $1 bills (no online transfers, checks, credit cards or any other tricks) and without requiring change. How did he do it?
A variation of this brain teaser includes laser printers (they were invented by Gary Starkweather) and bulletproof vests (invented by Casimir Zeglen using silk, though modern vests use Kevlar, so it’s halfway right).