Ages 12 & up (Item #33576) Double-sided, 4'' x 4'' cards. 1 Dot, 2 Dot & 3 Dot. Three levels of challenge. Cards offer three levels of difficulty, 1 Dot cards are easy, 2 Dot cards are medium and 3 Dot cards are tough. How to play Integers. Object of the game is to make positive 24. You can add, subtract, multiply and divide. Use all four numbers on a card, but use each number only once. Cards in this edition can can also be solved for negative 24. Each card has at least one solution to make positive 24 and negative 24.