2. Everyday Mathematics Partial-Products Multiplication

3. Partial-Products Multiplication Partial-products multiplication involves: Using the distributive property; Thinking about expanded notation; Using extended facts to calculate partial products; and Adding partial products to find the final answer. Everyday Mathematics

4. Partial-Products Multiplication Solve: 58 × 37 We begin by thinking about each number in expanded notation. 58 = 50 + 8 37 = 30 + 7 The key idea in partial products multiplication is to multiply each part of 58 by each part of 37. 50 × 30 50 × 7 Everyday Mathematics 8 × 30 8 × 7

5. Partial-Products Multiplication Solve: 58 × 37 58 × 37 We can find the partial product in any order. Here we start with 50 × 30. Everyday Mathematics We add the partial products together to find the answer. 50× 30 50× 7 8× 30 8× 7 Multiply: 1,500 350 240 + 56 2,146

6. Partial-Products Multiplication When children use partial-products they practice a variety of skills related to number sense and algebraic reasoning. For example: Identifying the place value of digits; Thinking about numbers in expanded notation; Applying the distributive property; Using multiplication fact extensions such as 50 × 30; and Adding to find the product. If children work from left to right, which is generally their inclination, they begin the problem solving process with a reasonable estimate of what the final answer should be. Everyday Mathematics