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# Do Now 11/15/11

Do Now 11/15/11. Take out your HW from last night. Text p. 102, #10-40 evens, #42, 43, 48, &amp; 49 Copy HW in your planner. Text p. 106, #10-44 evens

## Do Now 11/15/11

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1. Do Now 11/15/11 • Take out your HW from last night. • Text p. 102, #10-40 evens, #42, 43, 48, & 49 • Copy HW in your planner. • Text p. 106, #10-44 evens • In your journal, estimate an answer to the following situation. Potato salad costs \$0.99 per pound at the deli counter. About how much do you think 6.5 pounds of potato salad will cost?

2. 10) 39.05 12) 16.917 14) 15.33 16) 9.071 18) 2.24 20) 12.79 22) 4.47 24) 31.15 26) 8.25 minutes 28) -0.338 30) -17.361 32) -125.55 34) 48.46 36) 30.623 38) -2.6 40) 1,642.5 miles 42) 1.6 °F 43) 1915 48) B 49) G Homework Text p. 102, #10-40 evens, #42, 43, 48, & 49

3. Objective • SWBAT multiply decimals

4. Section 3-2Multiplying Decimals To multiply decimals, multiply as you would integers. To place the decimal point in the product count the number of decimal places in each factor. The product will have the same number of decimal places as the sum of the decimal places in the factors.

5. Find the product. 3.06 x 1.4 3.06 2 decimal places How many decimal places are in each number? x 1.4 1 decimal place 1224 How many decimal places are in the sum of both numbers? +3060 4284 4.284 3 decimal places will then be in the product!

6. Do you see a pattern? How many decimal places are in the factors? 12 1.2 0.12 x 4 x 0.4 x 4 48 4.8 48 000 How many decimal places are in the products? 0.048

7. Practice • 1) 1.46 x 0.02 • 2) 3.04 x 1.6 1) 1.46 x 0.02 0.0292 2) 3.04 x 1.6 1824 _+3040 4.864

8. “Multiplying Integers” Remember this? Rule #1 The product of two integers with the same sign is always POSITIVE! 8 x 3 = 24 -8 · (-7) = 56 Rule #2 The product of two integers with different signs is always NEGATIVE! -6 x 3 = -18 8(-4) = -32

9. Estimating Round each decimal to the nearest integer than find the product. -11.3 x 7.76 7.2(-4.36) -88 -28 -7.3(-6.72) -3.3(-3.3) 9 49

10. Find the product. -2.78 · 0.8 -2.78 2 decimal places How many decimal places are in each number? x 0.8 1 decimal place -2.224 -2224 How many decimal places are in the sum of both numbers? 3 decimal places will then be in the product!

11. 0.014 Find the product. -16 x 0.014 3 decimal places How many decimal places are in each number? x -16 0 decimal places 0084 How many decimal places are in the sum of both numbers? +0140 -0.224 -0224 3 decimal places will then be in the product!

12. “Real-Life” On average, Americans eat 0.25 lb of peanut butter per month. How many pounds of peanut butter are eaten by approximately 302 million Americans living in the United States per month? 302 x 0.25 1510 6040 75.50 million pounds of peanut butter are eaten by Americans each month

13. 24 Homework Text p. 106, #10-44 evens

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