Math Chapter 3: Multiply by 1-Digit Numbers

Chapter 3: Multiply by 2-Digit

Numbers

Lesson 3.1

Multiply by Tens

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Review Problem

The table shows the heights of some of the tallest

mountains in the world.

How many more feet high is Lhotse than Himalchuli?

Open Ended

Type your answer to the review problem here.

Solve the task below. Turn and talk
with your cooperative team and discuss

how you solved the problem.

Animation for a computer-drawn cartoon requires about 20 frames

per second. How many frames would need to be drawn for a

30-second cartoon?

One Way: Use place value.

Multiply. 30 × 20

You can think of 20 as 2 tens.

30 × 20 = 30 × ____ tens

______ tens

= ___________

Solve the task below. Turn and talk
with your cooperative team and discuss

how you solved the problem.

Animation for a computer-drawn cartoon requires about 20 frames

per second. How many frames would need to be drawn for a

30-second cartoon?

Another Way: Use the Associative Property.

You can think of 20 as 2 × 10.

30 × 20 = 30 × (2 × 10)

= (30 × 2) × 10
= ____ x ____

= ______

So, ______ frames would need to be drawn.

I can use place value and multiplication

properties to multiply by tens.

Page 146. Together: Other Ways! And Try This!

Math Partners: 147 # 2, 4

Independent: Page 147 #5, 6, 7, 8, 10, 11, 13

Done? Do the others! Or get help from reteach page

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Lesson 3.2

Estimate Products

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Review Problem

Samirah earns $24 per week babysitting. How

much will she earn in 30 weeks?

Solve the task below. Turn and talk
with your cooperative team and discuss

how you solved the problem.

On average, the Smith family opens the door of their refrigerator 32

times each day. There are 31 days in May. About how many times is the

refrigerator door opened in May?

One Way: Use rounding and mental math.

Estimate. 31 × 32

STEP 2 Use mental math

STEP 1 Round each factor

3 × 3 = 9 ← (basic fact)

____ x _____

3__ x 3__ = _____

So, the Smith family opens the refrigerator door about 900 times

during the month of May.

I can estimate products by

rounding or by using compatible

numbers.

Page 152. Together: Another Way! And Try This!, #2

Math Partners: 152-153 #1, 3 (share and show)

Independent: Page 153 #5, 7, 8, 10, 11, 13

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page

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Lesson 3.3

Investigate- Area Models and Partial Products

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Crayons-

blue, green,
yellow, pink

Review Problem

Carlo is in charge of buying uniforms for his baseball team.
One uniform costs $20. There are 14 players on his team.

How much will he spend for the uniforms?

I can use area models and partial

products to multiply 2-digit numbers.

Page 157!

Math Review
Friday, 11/4

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What would be the best estimate to use

to find 52 x 67?

There are 38 boxes of pens in Mrs.
Donnelly's supply cabinet. Each box

contains 100 pens. How many pens are

in the supply cabinet?

Dominic has 21 marbles. Tyler has 19

times as many marbles as Dominic. How

many marbles does Tyler have?

Sophia packed 34 bags of dog treats
for the animal shelter. She put 17 dog
treats in each bag. What is the total
number of dog treats Sophia packed?

Independent Time

Go Math packet

Multiplying Multiples of Ten
Find the product page

Lesson 3.4

Multiply Using Partial Products

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Review Problem

Use rounding to estimate the product 3 × 2,810.

Solve the task below. Turn and talk
with your cooperative team and discuss

how you solved the problem.

You know how to break apart a model to find partial products. How can you use

what you know to find and record a product?

Multiply. 34 × 57 Estimate. 30 × 60 = ________

50

7

30

4

Step 1:

Shade the

box to show

50 x 30.

50

7

Step 2:

Shade the

box to show

7 x 30.

30

4

50

7

30

4

Step 3:

Shade the

box to show

50 x 4.

50

7

30

4

Step 4:

Shade the

box to show

7 x 4.

I can use place value and partial

products to multiply 2-digit

numbers.

Page 164. Together: Example

Math Partners: 164 #1

Independent: Page 165 #2, 4, 5, 7, 9, 10, 15

Done? Do the others! Or get help from reteach

page

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Exit Ticket

Lesson 3.5

Multiply with Regrouping

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Review Problem

Use rounding to estimate the product of 42 and 29.

Solve the task below. Turn and talk
with your cooperative team and discuss

how you solved the problem.

By 1914, Henry Ford had streamlined his assembly line to make a Model T Ford car in 93
minutes. How many minutes did it take to make 25 Model Ts?
Use place value and regrouping. Multiply. 93 × 25 Estimate. 90 × 30 = _______
STEP 1
• Think of 93 as 9 tens and 3 ones.
• Multiply 25 by 3 ones.

STEP 2
• Multiply 25 by 9 tens.

STEP 3
• Add the partial products.

25
x 93
←3 x 25

25
x 93
75
←90 x 25
25
x 93
75
2,250

So, 93 × 25 is 2,325. Since ________ is
close to the estimate of _________, the

answer is reasonable.

I can use regrouping to multiply 2-digit

numbers.

Page 172. Together: Different Ways to Multiply, #1, 2

Math Partners: 172 #1, 2

Independent: Page 173 #3, 5, 7, 8, 10, 13

Done? Do the others! Or get help from reteach page

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Exit Ticket

Lesson 3.6

Choose a Multiplication Method

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Review Problem

The auditorium has 23 rows of seats. There are 18 seats

in each row. What is the total number of seats?

Solve the task below. Turn and talk
with your cooperative team and discuss

how you solved the problem.

Did you know using math can help prevent you from getting a sunburn?

The time it takes to burn without sunscreen multiplied by the SPF, or sun protection
factor, is the time you can stay in the sun safely with sunscreen.

If today’s UV index is 8, Izzy will burn in 15 minutes without sunscreen. If Izzy puts on
lotion with an SPF of 25, how long will she be protected?

One Way Use partial products to find 15 × 25.

25

x 15

←10 times 2 tens
←10 times 5 ones
←5 times 2 tens
←5 times 5 ones

Solve the task below. Turn and talk
with your cooperative team and discuss

how you solved the problem.

I can choose a method to multiply

2-digit numbers.

Page 178. Together: Another Way! And Try This!

Math Partners: 179 #1, 4

Independent: Page 179 #5, 7, 8, 10, 12

Done? Do the others! Or get help from reteach page

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Exit Ticket

Lesson 3.7

Problem Solving: Multiply 2-Digit

Numbers

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Review Problem

Tyler planted seeds that need warmth and sun for
8 weeks. There are 168 hours in a week. How many

hours are there in 8 weeks?

Solve the task below. Turn and talk
with your cooperative team and discuss

how you solved the problem.

During the 2010 Great Backyard Bird Count, an average of 42 bald eagles were counted in
each of 20 locations throughout Alaska. In 2009, an average of 32 bald eagles were counted
in each of 26 locations throughout Alaska. Based on this data, how many more bald eagles
were counted in 2010 than in 2009? Use the graphic organizer to help you solve the problem.

What do I need to find?
I need to find _____
bald eagles were counted
in 2010 than in 2009.

What information do
I need to use? In 2010, ______
locations counted an average of ______
bald eagles each. In 2009 _______
locations counted an average of
_______ bald eagles each.

How will I use the information?
I can solve simpler problems.
Find the number of bald eagles counted in ______.
Find the number of bald eagles counted in _______.
Then draw a bar model to compare the _____count to the
______ count

First, find the total number of bald eagles counted in 2010.
____× ____ =
____ bald eagles counted in 2010

• Next, find the total number of bald eagles counted in 2009.

= ____× ____ = ____ bald eagles counted in 2009

• Last, draw a bar model. I need to subtract.

840 − 832 = _______

So, there were _ more bald eagles counted in 2010 than in
2009.

I can use the strategy draw a

diagram to solve multistep

multiplication problems.

Page 184. Together: Try Another Problem!

Math Partners: 179 #1, 4

Independent: Page 185 #1, 2, 3

Done? Do the others! Or get help from reteach page

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Exit Ticket

Get Math Ready!

Math Review

Wednesday, 11/16

There are 58 boxes of pens in

Mrs. Greci's supply cabinet. Each

box contains 100 pens. How
many pens are in the supply

cabinet?

In July, traffic officers wrote an average of 34 tickets

each day. In August, they wrote an average of 47
tickets each day. How many more tickets did traffic
officers write in August than in July? (Hint: July and

August have 31 days each.)

Dominic runs on a treadmill for 45 minutes every

morning. His body uses about 12 calories per minute

to keep him moving. How many calories does

Dominic use during his run?

Grandma has 30 pages in her photo album. Each
page has 3 rows with 5 pictures in each row. How

many pictures are in Grandma's album?

People can join a skating club by paying $40
a year. The club had 67 members this year.
How much money in all did the skating club

collect from members this year?

Independent Time!

Multiplication facts in math channel

3.7 Reteach

Math Packet- Part 1- Find the Product

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Math Review

Thursday, 11/17

Izzy packed 34 bags of dog treats for

the animal shelter. She put 16 dog
treats in each bag. What is the total
number of dog treats Izzy packed?

A youth center sold raffle tickets to raise
money for supplies. They sold 52 books of
raffle tickets for $18 each. How much money

did the youth center raise?

Customers bought 45 shirts for $28
each. What is the total amount they

paid for the shirts?

People can join a scrabble club by paying
$40 a year. The club had 67 members this

year. How much money in all did the

scrabble club collect from members this

year?

There are 68 students in the book club.

Each student reads 14 books during summer
vacation. How many books do the students

read in all during summer vacation?

Independent Time!

Paper

3.7 Problem Solving- in packet

Multiplication facts in math channel

Get Math Ready!

Math Review
Friday, 11/18

Mr. Burke places orders for pencils with
the school emblem. The order includes
14 boxes of pencils, and each box holds
25 pencils. How many pencils does Mr.

Burke order?

On Friday, 17 buses left the bus station.

Each bus carried a full load of 53

passengers. Which is the best way to

estimate the total number of passengers

who left the bus station that day?

Tyler rents a kayak for 12 days. The rental

charge is $18 per day. Which is the best
estimate for the total cost of the kayak

rental?

34
x 12

23
x 47

68
x 26

Independent Time!

1.Math page

2. Odd in math packet- Find the product

3. Math games