Numerical Brain Teasers

Puzzle 1

Number Combinations

How to Play

Solve this puzzle by combining 3, 6, 5, and 5 to produce 23. Use only basic math operators. Keep these rules in mind: Use every digit exactly once in any order. You may only add, subtract, multiply, or divide. If you need to, add parentheses. Grade-school math only. You don’t need logs, factorials, decimals, exponentiation, or any other fancy math functions. Don’t rotate numbers. For example, a 9 is not a 6. Don’t put digits together; 1 and 4 don’t make 14. Programmers, remember that 3 divided by 2 is ...