Math Module 3 Multi-Digit Multiplication and Division Topic B: Multiplication by 10, 100, and 1,000...

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Math Module 3 Multi-Digit Multiplication and Division

Topic B: Multiplication by 10, 100, and 1,000

Lesson 5: Multiply multiples of 10, 100, and 1,000 by single digits

4.OA.1 4.OA.2 4.NBT.5 4.NBT.1

Lesson 5 Target

You will multiply multiples of 10,

100, and 1,000 by single digits

I can do this!

Can you draw something? What can you draw? The projection screen in the school auditorium is 5 times as long and 5 times as wide as the screen in the library. The screen in the library is 4 feet long with a perimeter of 14 feet. What is the perimeter of the screen in the auditorium? The projection screen in the school auditorium is 5 times as long and 5 times as wide as the screen in the library. The screen in the library is 4 feet long with a perimeter of 14 feet. What is the perimeter of the screen in the auditorium? What conclusions can you make from your drawing? Sat

FluencyGroup Count by Multiples of

10 and 100

Lesson 5Fluency

• Count by sevens to 70.

7 14 21 28 35 42 49 56 63 70• Now count by 7 tens. When I raise my hand,

stop counting.

7 tens 14 tens 21 tens

Say the number.

Continue!28 tens 35 tens 42 tens 420

49 tens 56 tens 63 tens

10 and 100

Lesson 5Fluency

• Count by 800 to 8,000.

800 1,600 2,400 3,200 4,000 4,800 5,600 6,400 7,200 8,000

• Now count by 8 hundreds. When I raise my hand, stop counting.

8 hundreds 16 hundreds 24 hundreds

Say the number.

Continue!32 hundreds 40 hundreds 48 hundreds

10 and 100

Lesson 5Fluency

• Count by 900 to 9,000.

900 1,800 2,700 3,600 4,500 5,400 6,300 7,200 8,100 9,000

• Now count by 9 hundreds. When I raise my hand, stop counting.

Say the number.

Continue!36 hundreds 45 hundreds 54 hundreds

(Write 3 × 2 = .) Say the multiplication sentence in unit form. S: 3 ones × 2 = 6 ones. T: Write the answer in standard form. S: (Write 6.) T: (Write 30 × 2 = .) Say the multiplication sentence in unit form. S: 3 tens × 2 = 6 tens. T: Write the answer in standard form. S: (Write 60.)

Lesson 5FluencyMultiply Units

• Say the multiplication sentence in unit form.

• 3 ones × 2 = 6 ones. • Write the answer in

standard form. • Did you write 6?

3 x 2 = ____

30 x 2 = ____• Say the multiplication

sentence in unit form. • 3 tens × 2 = 6 tens. • Write the answer in

• 3 hundreds × 2 = 6 hundreds.

• Write the answer in standard form.

• Did you write 600?

300 x 2 = ____

3,000 x 2 = ____• Say the multiplication sentence

in unit form. • 3 thousands × 2 = 6 thousands. • Write the answer in standard

form. • Did you write 6,000?

5 x 3 = ____

• 5 hundreds × 3 = 15 hundreds.

• Write the answer in standard form.

• Did you write 1,500?

500 x 3 = ____

5,000 x 3 = ____• Say the multiplication

sentence in unit form. • 5 thousands × 3 = 15

thousands. • Write the answer in

standard form. • Did you write 15,000?

• 5 hundreds × 8 = 40 hundreds. • Write the answer in standard

500 x 8 = ____

5,000 x 4 = ____• Say the multiplication sentence in

unit form. • 5 thousands × 4 = 20 thousands. • Write the answer in standard

5 x 8 = ____

Lesson 5Concept Development

Problem 1

2 ones × 4 2 tens × 4 2 hundreds × 4 2 thousands × 4

Show 2 ones × 4 on your place value chart. Circle each group of 2 ones.2 ones x 4 is?

Show 2 tens × 4 on your place value chart. Circle each group of 2 tens.2 tens x 4 is?

Problem 1

2 ones × 4 2 tens × 4 2 hundreds × 4 2 thousands × 4

What did you notice about multiplying 2 hundreds x 4 compared to 2 tens x 4?

With your partner, represent 2 hundreds × 4.

Circle each group of 2 hundreds.

There was the same

number of disks.

It was almost the same except I used disks that represented 1

hundred instead of 10.The value of the disks is in the hundreds,

so my answer is larger.

2 hundreds x 4 is?What do you think would happen if we multiplied 2 thousands x 4?

Problem 1b

3 tens × 3 3 hundreds x 3 3 thousands x 3

Show 3 tens × 3 on your place value chart. Circle each group of 3 tens.3 tens x 3 is?

Show 3 hundreds × 3 on your place value chart. Circle each group of 3 hundreds.3 hundreds x 3 is?

Thousands Hundreds Tens ones Thousands Hundreds Tens ones

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Problem 1b

3 tens × 3 3 hundreds x 3 3 thousands x 3

Thousands Hundreds Tens ones

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With your partner, represent 3 thousands × 3. Circle each group

of 3 thousands.

What did you notice about multiplying 3 thousands x 3 compared to 3 hundreds x 3?

There was the same

number of disks.

It was almost the same except I used disks that represented 1

hundred instead of 10.

The value of the disks is in the thousands, so my answer is larger.

2 hundreds x 4 is?What do you think would happen if we multiplied 2 thousands x 4?

Problem 2

8 x 2 8 x 20 8 x 200 8 x 2,000 With your partner, solve these multiplication problems in unit form.What patterns do you notice?All of the problems have 8 as a factor.The units are in order of the place value chart, smallest to largest.The unit we multiply is the same unit we get in our answer. Like 8 x 2 tens equals 16 tens and 8 x 2 hundreds is 16 hundreds.

Problem 2

8 x 2 8 x 20 8 x 200 8 x 2,000 What happens if we change the unit from 8 x 2 hundreds to

8 hundreds x 2? Does the answer change?

The answer stays the same even though the unit changed.

8 x 2 hundreds can be written 8 x (2 x 100)

8 hundreds x 2 can be written (8 x 100) x 2.

Problem 2b

5 x 2 5 x 20 5 x 200 5 x 2,000

With your partner, solve these multiplication problems in unit form.What patterns do you notice?All of the problems have 5 as a factor.The units are in order of the place value chart, smallest to largest.The unit we multiply is the same unit we get in our answer. Like 5 x 2 tens equals 10 tens and 5 x 2 hundreds is 10 hundreds.

5 x 2 ones = 10 ones5 x 2 tens = 10 tens5 x 2 hundreds = 10 hundreds5 x 2 thousands = 10 thousands

Lesson 5Concept

DevelopmentProblem 2b5 x 2 5 x 20 5 x 200 5 x 2,000

What happens if we change the unit from 5 x 2 hundreds to 5 hundreds x 2? Does the answer change?

The answer stays the same even though the unit changed.

5 x 2 hundreds can be written 5 x (2 x 100)

5 hundreds x 2 can be written (5 x 100) x 2.

Can you draw something? What can you draw? What conclusions can you make from your drawing?

RDW ReviewLesson 5

Read! Draw! Write!

Francisco plays a video game and earns 60 points for every coin he collects. He collected 7 coins. How many points did he earn for the coins that he collected? 2. Francisco also earns 200 points for every level he completes in the game. He completed 7 levels. How many points did he earn for the levels that he completed? 3. What was the total number of points that Francisco earned?

Lesson 5Concept DevelopmentProblem 3

Solve a word problem involving finding the sum of two different products of a single-digit number by a two- and three- digit multiple of 10

1. Francisco plays a video game and earns 60 points for every coin he collects. He collected 7 coins. How many points did he earn for the coins that he collected?

Solve a word problem involving finding the sum of two different products of a single-digit number by a two- and three- digit multiple of 10

• Francisco also earns 200 points for every level he completes in the game. He completed 7 levels. How many points did he earn for the levels that he completed?

• What was the total number of points that Francisco earned?

Solve a word problem involving 1,000 times as many.

At a concert, there were 5,000 people in the audience. That was 1,000 times the number of performers. How many performers were at the concert?Write an equation to solve for how many performers were at the concert. Solve using a method of your choice.

I know 1,000 times the number of performers is 5,000, so to solve the equation of p × 1,000 = 5,000, I know that there were 5 performers.

There are 1,000 times as many people in the audience, so I can divide 5,000 by 1,000 to find 5 performers.

Lesson 5

Problem Set

10 Minutes

Lesson 5

What pattern did you notice while solving

Problems 1, 2, and 3?

Lesson 5

Explain to your partner how you solved for the problems in the last row of Problem 5. Explain to your partner the value and importance of the

number zero in the factor and the product.

Lesson 5

DebriefLesson Objective:

Multiply multiples of 10, 100, and 1,000 by single

digits, recognizing patterns.

• Sometimes, we decompose using addition, such as saying 30 = 10 + 10 + 10, and sometimes we decompose using multiplication, such as saying 30 = 3 × 10. What are some possible decompositions of 24 using addition? Multiplication?

• What did you notice about 5 × 2, 5 × 20, 5 × 200, 5 × 2,000? Did you see that there is a “hidden” or “extra” zero because 5 × 2 ones is 1 ten, 5 × 2 tens is 10 tens, etc.

• What significant math vocabulary did we use today to communicate precisely? How did the last lesson prepare you for this lesson?

Exit Ticket

Lesson 4

Math Module 3 Multi-Digit Multiplication and Division Topic B: Multiplication by 10, 100, and 1,000...

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