5 Minute Check Complete in your notes. Find each sum 1. 4.9 + 3.0 2. 0.796 + 13 Find the difference. 3. 19.86 - 4.94 4. 82 – 67.18

5 Minute Check Complete in your notes. Find each sum 1. 4.9 + 3.0

5 Minute Check Complete in your notes. Find each sum 1. 4.9 + 3.0 4.9 + 3.0 7.9

5 Minute Check Complete in your notes. Find each sum 2. 0.796 + 13

5 Minute Check Complete in your notes. . Find each sum 2. 0.796 + 13 13.000 Annex zeros + 0.796 13.796

5 Minute Check Complete in your notes. Find the difference. 3. 19.86 - 4.94

5 Minute Check Complete in your notes. Find the difference. 3. 19.86 - 4.94 8 18 19.86 - 4.94 14.92

5 Minute Check Complete in your notes. Find the difference. 4. 82 – 67.18

5 Minute Check Complete in your notes. Find the difference. 4. 82 – 67.18 82.00 Annex zeros - 67.18 14.82

You make $8. 25 per hour at your job. Last week you worked 9 hours You make $8.25 per hour at your job. Last week you worked 9 hours. How much money did you make last week?

You make $8. 25 per hour at your job. Last week you worked 9 hours You make $8.25 per hour at your job. Last week you worked 9 hours. How much money did you make last week? 8.25 + 8.25 74.25

Lesson 3.2/3.3 Estimating and Multiplying Decimals by Whole Numbers Thursday, Aug 25 Lesson 3.2/3.3 Estimating and Multiplying Decimals by Whole Numbers

Multiplying Decimals by Whole Numbers Lesson 3.2 is estimation and will be incorporated into lessons 3.3 and 3.4.

Multiplying Decimals by Whole Numbers Objective: To understand how to estimate and find products of decimals and whole numbers.

Multiplying Decimals by Whole Numbers To multiply a decimal and whole number, multiply as normal and then place the decimal point.

Multiplying Decimals by Whole Numbers Find the product of 6 and .93. First, round the numbers to the nearest whole number and multiply to get an estimate.

Multiplying Decimals by Whole Numbers Find the product of 6 and .93. 6 is already a whole number, so rounding is not needed.

Multiplying Decimals by Whole Numbers Find the product of 6 and .93 Which is .93 closest to? 0 .93 1 Digits from 0 to 4 round down and digits from 5-9 round up.

Multiplying Decimals by Whole Numbers Find the product of 6 and .93 Which is .93 closest to? 0 .93 1 6 x 1 = 6, so 6 x .93 ≈ 6

Multiplying Decimals by Whole Numbers Because we are rounding, then multiplying the estimate could be further from the actual answer than yesterday.

Multiplying Decimals by Whole Numbers Find the product of 6 and .93 To Multiply Decimals. Step 1 – Stack the numbers with the number with the most digits on top. The decimals points do not need to be lined up!

Multiplying Decimals by Whole Numbers Find the product of 6 and .93 To Multiply Decimals. Step 1 – Stack the numbers with the number with the most digits on top. .93 x 6

Multiplying Decimals by Whole Numbers Find the product of 6 and .93 To Multiply Decimals. Step 2 – Multiply the digits without regard to the decimal point.

Multiplying Decimals by Whole Numbers Find the product of 6 and .93 To Multiply Decimals. Step 2 – Multiply the digits without regard to the decimal point. .93 x 6 558

Multiplying Decimals by Whole Numbers Find the product of 6 and .93 To Multiply Decimals. Step 3 – Determine the number of decimal places in the factors to locate the decimal point in the product.

Multiplying Decimals by Whole Numbers Find the product of 6 and .93 To Multiply Decimals. Step 3 – Determine the number of decimal places in the factors to locate the decimal point in the product. .93 2 decimal places x 6 0 decimal places 5.58 2 decimal places Is this a reasonable answer?

Multiplying Decimals by Whole Numbers Find the product of 6 and .93 To Multiply Decimals. Step 3 – Determine the number of decimal places in the factors to locate the decimal point in the product. .93 2 decimal places x 6 0 decimal places 5.58 2 decimal places Is this a reasonable answer? Yes, 5.58 ≈ 6

Multiplying Decimals by Whole Numbers Estimate and Multiply. Show all work and circle all answers. 5 x 10.2 ≈ Estimate?

Multiplying Decimals by Whole Numbers Estimate and Multiply. Show all work and circle all answers. 5 x 10.2 ≈ 50 Step 1 ?

Multiplying Decimals by Whole Numbers Estimate and Multiply. Show all work and circle all answers. 5 x 10.2 ≈ 50 10.2 x 5 Step 2 ?

Multiplying Decimals by Whole Numbers Estimate and Multiply. Show all work and circle all answers. 5 x 10.2 ≈ 50 10.2 x 5 510 Step 3 ?

Multiplying Decimals by Whole Numbers Estimate and Multiply. Show all work and circle all answers. 5 x 10.2 ≈ 50 10.2 1 decimal place x 5 0 decimal place 51.0 1 decimal place Everything inside the green square is required on todays assignment.

Multiplying Decimals by Whole Numbers Estimate and Multiply. Show all work and circle all answers. 5 x 10.2 ≈ 50 10.2 1 decimal place x 5 0 decimal place 51.0 1 decimal place Does this seem reasonable?

Multiplying Decimals by Whole Numbers Estimate and Multiply. Show all work and circle all answers. 7 x 7.5 ≈ Do this on your own.

Multiplying Decimals by Whole Numbers Estimate and Multiply. Show all work and circle all answers. 7 x 7.5 ≈56 7.5 1 decimal place x 7 0 decimal place 52.5 1 total decimal place Does this seem reasonable?

Multiplying Decimals by Whole Numbers Estimate and Multiply. Show all work and circle all answers. 1.2 x 45 ≈ Do this on your own.

Multiplying Decimals by Whole Numbers Estimate and Multiply. Show all work and circle all answers. 1.2 x 45 ≈ 45 1.2 x 45 60 480 54.0 Does this seem reasonable?

Multiplying Decimals by Whole Numbers Estimate and Multiply. Show all work and circle all answers. 2 x 0.034 ≈ Do this on your own.

Multiplying Decimals by Whole Numbers Estimate and Multiply. Show all work and circle all answers. 2 x 0.034 ≈ 0 .034 x 2 0.068 Does this seem reasonable? Warning – when multiplying whole numbers by decimals less the 0.5, estimates become more difficult.

Multiplying Decimals by Whole Numbers Estimate and Multiply. Show all work and circle all answers. 27 x 0.27 ≈ Do this on your own.

Multiplying Decimals by Whole Numbers Estimate and Multiply. Show all work and circle all answers. 27 x 0.27 ≈ 0 27 x .27 189 540 7.29

Multiplying Decimals by Whole Numbers A sheet of printer paper is 8.5 inches by 11 inches. What is the area of the paper? (Hint: area = length x width) (Do this on your own)

Multiplying Decimals by Whole Numbers A sheet of printer paper is 8.5 inches by 11 inches. What is the area of the paper? (Hint: area = length x width) 8.5 x 11 ≈ 99 8.5 x 11 85 850 93.5 9

Multiplying Decimals by Whole Numbers A batch of trail mix calls for 1.2 pounds of dry cereal. Kyle is making 5 batches of trail mix. He already has 2 pounds of dry cereal. How many more pounds of dry cereal does he need? Do this on your own.

Multiplying Decimals by Whole Numbers A batch of trail mix calls for 1.2 pounds of dry cereal. Kyle is making 5 batches of trail mix. He already has 2 pounds of dry cereal. How many more pounds of dry cereal does he need? 1.2 x 5 ≈ 5 1.2 x 5 6.0 He already has 2, 6 – 2 = 4 pounds 1

Multiplying Decimals by Whole Numbers A batch of trail mix calls for 1.2 pounds of dry cereal. Kyle is making 5 batches of trail mix. He already has 2 pounds of dry cereal. How many more pounds of dry cereal does he need? 1.2 1 decimal place x 5 6.0 1 decimal place 6 lbs (what he needs) – 2 lbs (he has) = 4 lbs Is this a reasonable answer?

Multiplying Decimals by Whole Numbers A bee hummingbird has a mass of 1.8 grams. How many grams are 6 hummingbirds and a 4 gram nest? Do this on your own.

Multiplying Decimals by Whole Numbers A bee hummingbird has a mass of 1.8 grams. How many grams are 6 hummingbirds and a 4 gram nest? 1.8 1 decimal place x 6 10.8 1 decimal place + 4 gram nest 14.8 g total

Multiplying Decimals by Whole Numbers Find two different ways to find the value of the expression 5.7 x 1.17 x 100 that do not require you to first multiply 5.7 x 1.17. Do this on your own.

Multiplying Decimals by Whole Numbers Find two different ways to find the value of the expression 5.7 x 1.17 x 100 that do not require you to first multiply 5.7 x 1.17. Two possible answers. 1.17 x 100 = 117 x 5.4 = 666.9 5.7 x 100 = 570 x 1.17 = 666.9

Multiplying Decimals by Whole Numbers Use the product of 123 x 47 to find the product of 123 x 0.47. Explain the difference between the two products. Do this on your own.

Multiplying Decimals by Whole Numbers Use the product of 123 x 47 to find the product of 123 x 0.47. Explain the difference between the two products. 123 123 x 47 x .47 861 861 4920 4920 5781 57.81 The products are different by a factor of 100.

Multiplying Decimals by Whole Numbers Your friend thinks that 1.5 x 8 = 1.20 because you do not count the zero when placing the decimal point. Is your friend correct? Explain. Do this on your own.

Multiplying Decimals by Whole Numbers Your friend thinks that 1.5 x 8 = 1.20 because you do not count the zero when placing the decimal point. Is your friend correct? Explain. No, you need the zero to place the decimal point. But you can “unannex” the zero after you place the decimal point.

Division Divide. Show all work and circle the answer. Express all remainders as fractions. 432 ÷ 3

Division Divide. Show all work and circle the answer. Express all remainders as fractions. 432 ÷ 3 = 144 144 3) 432 -3 13 -12 12 1 x 3 = 3 6 9 12 15 18 21 24 27

Division Divide. Show all work and circle the answer. Express all remainders as fractions. 371 ÷ 4

Division Divide. Show all work and circle the answer. Express all remainders as fractions. 371 ÷ 4 = 92 3 4 092 4) 371 -36 11 -8 3 1 x 4 = 4 8 12 16 20 24 28 32 36

Multiplying Decimals by Whole Numbers Agenda Notes Skills Practice 3.3 Odd numbers only! Due by the end of class. When complete work on MobyMax Mid-Chapter 3 Quiz Monday, Aug 29