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 Find the difference – 67.18

5 Minute Check Complete in your notes. Find each sum

5 Minute Check Complete in your notes. . Find each sum Annex zeros

5 Minute Check Complete in your notes. Find the difference

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

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

5 Minute Check Complete in your notes. Find the difference – Annex zeros

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.

Objective: To understand how to estimate and find products of decimals and whole numbers.

To multiply a decimal and whole number, multiply as normal and then place the decimal point.

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

Find the product of 6 and is already a whole number, so rounding is not needed.

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

Find the product of 6 and .93 Which is .93 closest to? x 1 = 6, so 6 x .93 ≈ 6

Because we are rounding, then multiplying the estimate could be further from the actual answer than yesterday.

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!

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

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

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

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.

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 decimal places x 6 0 decimal places decimal places Is this a reasonable answer?

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 decimal places x 6 0 decimal places decimal places Is this a reasonable answer? Yes, 5.58 ≈ 6

Estimate and Multiply. Show all work and circle all answers. 5 x 10.2 ≈ Estimate?

Estimate and Multiply. Show all work and circle all answers. 5 x 10.2 ≈ 50 Step 1 ?

Estimate and Multiply. Show all work and circle all answers. 5 x 10.2 ≈ x 5 Step 2 ?

Estimate and Multiply. Show all work and circle all answers. 5 x 10.2 ≈ x Step 3 ?

Estimate and Multiply. Show all work and circle all answers. 5 x 10.2 ≈ decimal place x 5 0 decimal place decimal place Everything inside the green square is required on todays assignment.

Estimate and Multiply. Show all work and circle all answers. 5 x 10.2 ≈ decimal place x 5 0 decimal place decimal place Does this seem reasonable?

Estimate and Multiply. Show all work and circle all answers. 7 x 7.5 ≈ Do this on your own.

Estimate and Multiply. Show all work and circle all answers. 7 x 7.5 ≈ decimal place x 7 0 decimal place total decimal place Does this seem reasonable?

Estimate and Multiply. Show all work and circle all answers. 1.2 x 45 ≈ Do this on your own.

Estimate and Multiply. Show all work and circle all answers. 1.2 x 45 ≈ x Does this seem reasonable?

Estimate and Multiply. Show all work and circle all answers. 2 x ≈ Do this on your own.

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

Estimate and Multiply. Show all work and circle all answers. 27 x 0.27 ≈ Do this on your own.

Estimate and Multiply. Show all work and circle all answers. 27 x 0.27 ≈ 0 27 x

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)

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 ≈ x 9

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.

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 ≈ x He already has 2, 6 – 2 = 4 pounds 1

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? decimal place x decimal place 6 lbs (what he needs) – 2 lbs (he has) = 4 lbs Is this a reasonable answer?

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.

A bee hummingbird has a mass of 1.8 grams. How many grams are 6 hummingbirds and a 4 gram nest? decimal place x decimal place + 4 gram nest 14.8 g total

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 Do this on your own.

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 Two possible answers x 100 = 117 x 5.4 = x 100 = 570 x 1.17 = 666.9

Use the product of 123 x 47 to find the product of 123 x Explain the difference between the two products. Do this on your own.

Use the product of 123 x 47 to find the product of 123 x Explain the difference between the two products x 47 x The products are different by a factor of 100.

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.

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 = 092 4) 371 -36 11 -8 3 1 x 4 = 4 8 12 16 20 24 28 32 36

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

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.

Similar presentations

Presentation on theme: "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."— Presentation transcript:

Similar presentations

About project

Feedback

Log in

Auth with social network:

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.

Similar presentations

Presentation on theme: "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."— Presentation transcript:

Similar presentations

About project

Feedback