Multiply by 12

Learning Objectives Use the 'break-apart' strategy (10 + 2) to solve multiplication problems with 12. Solve for the product of any single-digit number multiplied by 12. Use repeated addition to find the answer to a 'times 12' problem. Identify real-world situations where multiplying by 12 is useful. Solve word problems that involve multiplying by 12. Explain the connection between multiplying by 10, multiplying by 2, and multiplying by 12. Have you ever bought a dozen eggs or looked at a clock? 🥚 You're already using the number 12! Today, we are going to learn a special trick to multiply any number by 12. This skill will help you solve bigger math problems much faster and is super useful in everyday life. Real-World Applications Calculating the...

TermDefinitionExample FactorA number that is multiplied by another number to find a product.In the problem 5 x 12 = 60, the numbers 5 and 12 are the factors. ProductThe answer you get when you multiply two or more numbers together.In the problem 5 x 12 = 60, the number 60 is the product. DozenA special word that means a group of exactly 12 things.A carton of eggs usually has one dozen, which is 12 eggs. Repeated AdditionAdding the same number over and over again. It's another way to think about multiplication.3 x 12 is the same as adding 12 three times: 12 + 12 + 12 = 36. Break-Apart StrategyA trick where you break a bigger number into smaller, easier numbers to work with before you multiply.To solve 4 x 12, you can break 12 into 10 and 2. Then you solve 4 x 10 and 4 x 2, and add the...

The Break-Apart Rule (The 10 + 2 Trick) n \times 12 = (n \times 10) + (n \times 2) This is the easiest way to multiply by 12. First, multiply your number (n) by 10. Then, multiply your number (n) by 2. Finally, add those two answers together to get your final product. The Repeated Addition Rule n \times 12 = 12 + 12 + ... + 12 \text{ (n times)} You can always find the answer to a multiplication problem by adding the number 12 to itself the correct number of times. This is great for checking your work. The Commutative Property 12 \times n = n \times 12 This rule reminds us that you can switch the order of the factors and the product will stay the same. 12 x 5 is the same as 5 x 12.