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Lesson 9.8: Multiplication of Decimals Mental Math estimate the product and write the number model you used to solve it Example: 9 * 18 You write: or 11 * 42 63 * 63 9 * 20 = 180 10 * 18 = 180 22 * 76 98 * 59 28 * 49 72 * 414 Math Message Solve the problem at the top of MJ page 268 Estimating Products of Decimals We will learn to find the product of decimals On your slate, estimate each product. Show your work. 11 * 2.8 110 * 2.8 11 * 0.28 11 * 2.8 110 * 2.8 11 * 0.28 Which problem is most likely to have the product 30.8? How do you know? 110 * 2.8 = 308 Where would you place the decimal point? How do you know? 11 * 0.28 = 308 Where would you place the decimal point? How do you know? Estimate the cost of 5 calculators Multiply 5 * 929 Let’s use our estimate to place the decimal. What are the steps to estimating the product of decimals? Partnership Work MJ p 268 Math Journal page 269 What did we learn…