1st Grade -...

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1st Grade

Two Digit Subtraction

2015-11-30

www.njctl.org

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Table of Contents click on the topic to go to that section

- Subtracting Ten on a Number Grid- Subtracting Ten Patterns

- Patterns When Subtracting Multiples of Ten

- Two Digit Minus One Digit

- Subtracting Ten from Multiples of Ten in Our Head

- Two Digit Minus Two Digit- Two Digit Minus Two Digit Pt. 2

- Word Problems

- Subtracting Ten from Multiples of Ten with Blocks

- Subtracting Multiples of Ten with Blocks

- Subtracting Ten with Blocks

- Subtracting Multiples of Ten on a Number Grid

- Extra Word Problems (If needed)

- Lab: Subtraction Dice Roll

- Lab: Subtraction Spin

- Lab: Subtraction Around the Room

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Standards for Mathematical Practices

MP 8 Look for and express regularity in repeated reasoning.

MP 1 Make sense of problems and persevere in solving them.

MP 2 Reason abstractly and quantitatively.

MP 3 Construct viable arguments and critique the reasoning of others.

MP 4 Model with mathematics.

MP 5 Use appropriate tools strategically.

MP 6 Attend to precision.

MP 7 Look for and make use of structure.

Click on each standard to bring you to an example of how to meet

this standard within the unit.

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Subtracting 10 from Multiples of 10 with Blocks

Click to return to Table of Contents

Slide 5 (Answer) / 225

Subtracting 10 from Multiples of 10 with Blocks


Teac

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[This object is a teacher notes pull tab]

Students will need base ten blocks and place value charts for this lesson.

http://www.njctl.org

http://www.njctl.org

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How is subtracting 6 - 1 similar to 60 - 10?

Class Discussion


How is subtracting 6 - 1 similar to 60 - 10?

Class Discussion

[This object is a pull tab]

Teac

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Discuss how 6 cubes take away 1 cube make 5 cubes.

Then 6 longs take away 1 long make 5 longs. They

both have the same amount of blocks but the blocks are

worth different values.

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1 The base ten blocks show 20 - 10 = 10

True

False


1 The base ten blocks show 20 - 10 = 10

True

False


Ans

wer

False

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2 60 - 10 = ______

A 5

B 50

C 70


2 60 - 10 = ______

A 5

B 50

C 70


Ans

wer

A

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3 8 tens - 1 ten = ______ tens


3 8 tens - 1 ten = ______ tens


Ans

wer

7

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4 Which block should we use to show

50 - 10 = ______

A 40

B cube

C long


4 Which block should we use to show

50 - 10 = ______

A 40

B cube

C long[This object is a pull tab]

Ans

wer

C


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Subtracting Ten From Multiples of Ten in Our Heads


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10 20 30 40 50

60 70 80 90 100

100, ____, ____, ____, ____, ____, ____, ____, ____, ____

Let's Count By Tens

Now let's write them backwards starting with 100!


10 20 30 40 50

60 70 80 90 100

100, ____, ____, ____, ____, ____, ____, ____, ____, ____

Let's Count By Tens

Now let's write them backwards starting with 100!


Teac

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otes Click on each long to make it

disappear and reveal the number. Take lots of time

during this lesson to practice counting backwards by 10.

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Let's Count Back By Tens. Start 100!

100 90 80 70 60

50 40 30 20 10

Now let's write them forwards starting with 10!

10, ______, ______, ______, ______,

______, ______, ______, ______, ______

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(Answer) / 225

Let's Count Back By Tens. Start 100!

100 90 80 70 60

50 40 30 20 10

Now let's write them forwards starting with 10!

10, ______, ______, ______, ______,

______, ______, ______, ______, ______

Teac

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Click on each dime to make the number appear.

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100, 90, 80, 70, 60, 50, 40, 30, 20, 10What pattern do you see

when counting backwards?

100, 90, 80, 70, 60, 50, 40, 30, 20, 10

Patterns when Counting


100, 90, 80, 70, 60, 50, 40, 30, 20, 10What pattern do you see

when counting backwards?

100, 90, 80, 70, 60, 50, 40, 30, 20, 10

Patterns when Counting


Teac

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&

Mat

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actic

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MP 7 Look for and make use of structure

Ask students to identify the pattern they see and how they

think the pattern could help them.

Click on the question to show the numbers with the pattern

highlighted.

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Practice

50, 40, 30, ______, ______

90, 80, 70, ______, ______

80, 70, 60, ______, ______

100, 90, 80, ______, ______

60, 50, 40, ______, ______

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When subtracting ten,

the tens place goes down by 1.

50 - 10 = 40

70 - 10 = 60

Subtracting


When subtracting ten,

the tens place goes down by 1.

50 - 10 = 40

70 - 10 = 60

Subtracting

Teac

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Discuss how 5 went down to 4 which is 1 less and how 7 went down to 6 which is one

less.

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Practice

80 - 10 = ______

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Practice

40 - 10 = ______

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60 - 10 = ______

Practice

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6 30 - 10 = ______

A 40

B 20

C 30


6 30 - 10 = ______

A 40

B 20

C 30


Ans

wer

B

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7 10 - 10 = ______

A 20

B 0

C 10

(Answer) / 225

7 10 - 10 = ______

A 20

B 0

C 10


Ans

wer

B

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8 70 - 10 = ______

A 60

B 80

C 10


8 70 - 10 = ______

A 60

B 80

C 10


Ans

wer

A

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9 90 - 10 =


9 90 - 10 =


Ans

wer

80

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10 20 - 10 =

(Answer) / 225

10 20 - 10 =


Ans

wer

10

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Slide 39 / 225 Slide 40 / 225

Subtracting 10 with Blocks



Subtracting 10 with Blocks


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(Answer) / 225 Slide 42 / 225



(Answer) / 225 Slide 45 / 225



(Answer) / 225 Slide 48 / 225

11 34 - 10 = 24

Yes

No

** Use blocks at your desk to help you **


11 34 - 10 = 24

Yes

No

** Use blocks at your desk to help you **[This object is a pull tab]

Ans

wer

Yes

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(Answer) / 225 Slide 51 / 225


15 82 - 10 = ______



15 82 - 10 = ______



Ans

wer

72

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Subtracting Ten on a Number Grid



Subtracting Ten on a Number Grid


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Before starting this lesson, review

multiples of 10 with the students by

counting by 10 and listing multiples of

10 on the board. All students will need a

number grid.

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Subtracting 10 is very easy when using a number grid.Find the number you are subtracting 10 from on the number

grid and circle it. Then move up one box.

Number Grid

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24 - 10 = 14


24 - 10 = 14

Teac

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Discuss why 24 is circled. Allow students to count the boxes one jump at a time to confirm that one jump up is

that same as ten jumps.

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40 - 10 = 30

Find the first number on the number grid.Since we are subtracting from a multiple of 10, the

number will always be in the last row.Then, move up one jump.

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Let's try another one56 - 10 =

First, find the number on the number grid.Then jump up one.

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What number should we circle?

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What number should we circle?

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Class Discussion

John used his number grid to help solve the subtraction sentence below. He said the answer is

25. Is he correct? What did he do wrong?

24 - 10 =


Class Discussion

John used his number grid to help solve the subtraction sentence below. He said the answer is

25. Is he correct? What did he do wrong?

24 - 10 =


Mat

h Pr

actic

e

MP 3 Construct viable arguments and critique the

reasoning of others

In small groups give students time to voice their opinions about the problems. Then

allow a whole class discussion on why he is or is not correct.

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16 25 - 10 = 24

Yes

No


16 25 - 10 = 24

Yes

No


Ans

wer

No

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17 39 - 10 = 49

True

False


17 39 - 10 = 49

True

False


Ans

wer

False

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18 58 - 10 = ______

A 68

B 48

C 58


18 58 - 10 = ______

A 68

B 48

C 58


Ans

wer

B

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19 34 - 10 =


19 34 - 10 =


Ans

wer

24

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20 74 - 10 =


20 74 - 10 =


Ans

wer

64

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Subtracting 10 Patterns


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46- 10 36

When subtracting 10,the tens place always goes down 1 and the ones place

stays the same.

Tens

One

s

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24- 10 14

39- 10 29

77- 10 67

62- 10 52


24- 10 14

39- 10 29

77- 10 67

62- 10 52

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Discuss the pattern in the tens place.

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6 4- 1 0

5 6- 1 0

3 7- 1 0

2 3- 1 0

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Let's Practice

65 - 10 = _____

85 - 10 = _____

38 - 10 = _____

61 - 10 = _____Slide 76 (Answer) / 225

Let's Practice

65 - 10 = _____

85 - 10 = _____

38 - 10 = _____

61 - 10 = _____[This object is a pull tab]

Mat

h Pr

actic

e

MP 8 Look for and express regularity in repeated reasoning

Ask students if they can find a shortcut to solve these

problems and how it would make it easier.

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Web Practice

Click here for a game. Select level 3

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21 59 - 10 = 69

True

False


21 59 - 10 = 69

True

False


Ans

wer

False

http://www.sheppardsoftware.com/mathgames/fruitshoot/fruitshoot_subtraction.htm



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22 67 - 10 = ______

A 57

B 77

C 66


22 67 - 10 = ______

A 57

B 77

C 66


Ans

wer

A

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23 31 - 10 = ______

A 41

B 21

C 30


23 31 - 10 = ______

A 41

B 21

C 30


Ans

wer

B

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24 45 - 10 =


24 45 - 10 =


Ans

wer

35

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25 32 - 10 =


25 32 - 10 =


Ans

wer

22

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Subtracting Multiples of 10with Blocks



Subtracting Multiples of 10with Blocks


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26 Does 40 - 20 = 10?

Yes

No

** Use your blocks to help you **


26 Does 40 - 20 = 10?

Yes

No



Ans

wer

No

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27 80 - 70 = 10

True

False



27 80 - 70 = 10

True

False

** Use your blocks to help you **[This object is a pull tab]

Ans

wer

True

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28 40 - 30 = ______

A 20

B 70

C 10



28 40 - 30 = ______

A 20

B 70

C 10



Ans

wer

C

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29 90 - 60 = ______



29 90 - 60 = ______


Ans

wer

30

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30 50 - 50 = ______



30 50 - 50 = ______


Ans

wer

0

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Subtracting Multiples of Ten on a Number Grid



Subtracting Multiples of Ten on a Number Grid


Teac

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otes


Before starting this lesson, review

multiples of 10 with the students by

counting by 10 and listing multiples of 10

on the board.

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Let's warm up our brains by skip counting by 10's

using different voices.

Can you count by 10s in a:

- scary voice?

- mommy voice?

- baby voice?

- daddy voice?

10, 20, 30

Count by 10's

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To subtract multiples of 10 on a number grid, you count by 10s.

60 - 40 = ______Find the first number on the grid and circle it.

Count by 10s and move up one jump for each number you say. Stop when you say the second number in the subtraction

sentence. The number you land on is the answer.

10203040

Subtract

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Count by 10 as you move up to solve the subtraction sentence.

80 - 20 = ______What number should you circle?

SubtractSlide 102 (Answer) / 225



Subtract

Teac

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Have students work through these problems at

their seats as another student demonstrates it on the board.

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Subtract

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Subtract

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90 - 20 = ______

Subtract

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50 - 40 = ______

Subtract


50 - 40 = ______

Subtract


Mat

h Pr

actic

e

MP 5 Use appropriate tools strategically

Have students verbally explain to a partner how they

would use the grid to help them solve the problem.

Have a student then explain each step as they solve the

problem at the board.

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31 60 - 20 = ______

A 80

B 50

C 40

** Use your number grid to help you **


31 60 - 20 = ______

A 80

B 50

C 40



Ans

wer

C

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32 When subtracting multiples of 10, we need to count by ______.

A 1

B 5

C 10

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32 When subtracting multiples of 10, we need to count by ______.

A 1

B 5

C 10


Ans

wer

C

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33 90 - 40 = ______

A 40

B 50

C 60



33 90 - 40 = ______

A 40

B 50

C 60

** Use your number grid to help you **[This object is a pull tab]

Ans

wer

B

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34 50 - 30 = ______



34 50 - 30 = ______


Ans

wer

20

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35 20 - 10 = ______


(Answer) / 225

35 20 - 10 = ______


Ans

wer

10

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Patterns When SubtractingMultiples of Ten


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Let's Count By 10s

What digit changes when we count by 10s?


Let's Count By 10s

What digit changes when we count by 10s?

Teac

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Write the numbers on the lines.

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What number is this?

Take 20 away and what number does it become?

What digit changed?




What digit changed?

Teac

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Cross out 2 longs and have the students recount.

Discuss how the tens place changed but not the ones since we subtracted 10s.

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30 - 20 = 10


30 - 20 = 10

Teac

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Review how the tens place changed when we subtracted

10.

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What digit changed?


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What digit changed?

Take ten away and what number does it become?

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Count back by 10s

60, 50, ___, ___, ___, ___

70, 60, ___, ___, ___, ___

40, 30, ___, ___, ___, ___

60, 50, ___, ___, ___, ___


Count back by 10s

60, 50, ___, ___, ___, ___

70, 60, ___, ___, ___, ___

40, 30, ___, ___, ___, ___

60, 50, ___, ___, ___, ___

Teac

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Review that when counting by 10s, the tens place goes down 1 and the ones place

stays the same.

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40

206030

8070

What number is 20 less?

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36 10 less than 50 is 5?

True

False



True

False


Ans

wer

False

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Yes

No

(Answer) / 225


Yes

No


Ans

wer

No

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38 What is 30 less than 40?




Ans

wer

10

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Ans

wer

10

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40 70 - 40 = ?

QUIZ

(Answer) / 225

40 70 - 40 = ?

QUIZ


Ans

wer

30

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Lab: Subtracting 10 Dice Roll

Directions:· Split students into groups of 2 and give each group 2 dice· Each student rolls 1 dice and they work together to build the largest two digit number with their dice· Students write the number in the box on their worksheet· Students subtract 10 and write the answer on the line


Click here for more information.

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Two Digit Minus One Digit


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When subtracting a 1 digit number from a 2 digit number, it is very important to line them up on top of

each other.

36 - 2

All of the numbers should be on the right

Subtracting

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(Answer) / 225

When subtracting a 1 digit number from a 2 digit number, it is very important to line them up on top of

each other.

36 - 2

All of the numbers should be on the right

Subtracting

Teac

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You may need to review digits vs numbers with the

kids prior to this lesson. In addition, review place value.

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Can you line up these numbers?

24- 4

Subtracting

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58- 6

Subtracting

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73- 1

Subtracting



73- 1

Subtracting


Mat

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e

MP 6 Attend to precision

Ask students what would happen if they don't line the

numbers up correctly.

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Once the numbers are lined up,subtract the ones first and then the tens.

2 7- 4

One

s

It may help you to draw a line between the tens and ones.

3

When there is no digit in the tens

place, we know it is a 0. 0

2It is important to line up

the answer as well!!

Subtracting

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Remember to subtract the ones first and then the tens!!!

5 3- 1

One

s


When there is no digit in the tens place, we know it is a 0. 0

It is important to line up the answer as well!!

Subtracting

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79- 8

One

s


It is important to line up the answer as well!!

Subtracting

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65- 3

One

s


It is important to line up the answer as

well!!

Subtracting

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9 6- 5

Subtract

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3 5- 3

Subtract

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2 6- 2

Subtract

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2 6- 2

Subtract


Mat

h Pr

actic

e

MP 2 Reason abstractly and quantitatively

Ask students if the answer is going to be more than or less than 26. Have them explain

their reasoning.

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Web Practice


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41 3 9 - 7

A 32

B 31

C 36


41 3 9 - 7

A 32

B 31

C 36 [This object is a pull tab]

Ans

wer

A

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42 1 4 - 3

A 17

B 7

C 11


42 1 4 - 3

A 17

B 7

C 11[This object is a pull tab]

Ans

wer

C




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43 7 7 - 5


43 7 7 - 5


Ans

wer

72

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44 8 4 - 3


44 8 4 - 3


Ans

wer

81

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45 2 7 - 2


45 2 7 - 2


Ans

wer

25

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Two Digit Minus Two Digit


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What number is represented below?


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24

Now we want to take away 11

When we take away we always start with the bigger number.


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tens ones

2 41 1-

First subtract the ones by crossing them out.

How many are left?

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Next cross out the tens

How many are left?

3

tens ones

2 41 1-

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tens ones

2 41 1-

31


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What number is shown below?


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47

Now we want to take away 23

Remember we always start with the bigger number.


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tens ones

4 72 3-

First cross out the ones

How many are left?

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tens ones

4 72 3-

Next cross out the tens

How many are left?

4

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tens ones

4 72 3-

42


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tens ones

3 4 3 1-

First cross out the ones.Next cross out the tens.What is the answer?

Subtract

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tens ones

6 8 4 7-


Subtract

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tens ones

5 2 3 2-


Subtract

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tens ones

4 9 2 7-


Subtract

Slide 165 / 225Roll the two set of dice.

Place the larger number at the top of the problem.Place the second number under the first number. Subtract.

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46 3 5 - 1 2 2 3

Yes

No


46 3 5 - 1 2 2 3

Yes

No[This object is a pull tab]

Ans

wer

Yes

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47 6 9 - 5 6 3 3

Yes

No


47 6 9 - 5 6 3 3

Yes

No [This object is a pull tab]

Ans

wer

No

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48 2 4 - 1 2

A 36

B 2

C 12


48 2 4 - 1 2

A 36

B 2


Ans

wer

C

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Draw base ten blocks to help you solve this problem.

49 3 6 - 2 2

A 14

B 24

C 58



49 3 6 - 2 2

A 14

B 24


Ans

wer

A

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50 7 8 - 4 3



50 7 8 - 4 3



Ans

wer

35

Slide 171 / 225 Slide 172 / 225

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Two Digit Minus Two Digit Pt 2


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34- 23

When subtracting two digit numbers, it is important to still line up the numbers.

34- 23

Subtracting Two Digit Numbers


34- 23

When subtracting two digit numbers, it is important to still line up the numbers.

34- 23


Teac

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otes


Show students how the ones and tens are lined up. Also, point out where the minus

sign is. Have students practice writing the problem

on their own paper to be sure they are lining the numbers up correctly.

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3 42 3-

Once the numbers are lined up,draw a line between the tens and ones.

First subtract the ones.

Think of it as two smaller subtraction problems

One

s

Tens


Slide 176 / 225

3 42 3-

After you subtract the ones,subtract the tens!

One

s

Tens

11Don't forget to line up the answer too!


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7 6 4 5-

Let's try one!

One

s

Tens

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(Answer) / 225

7 6 4 5-

Let's try one!

One

s

Tens

Teac

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otes


Have the students practice lining up the numbers by pulling

the digits to the correct location. Once the numbers are lined up, have them mark the ones by either circling the ones or drawing an arrow on

top to remind them to subtract the ones first.

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3 6 5 2-

Practice

One

s

Tens

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1 46 4 -

Practice

One

s

Tens

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5 72 1-

Practice

One

s

Tens

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6 53 3-

Practice

One

s

Tens

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7 22 0-

Practice

One

s

Tens

(Answer) / 225

7 22 0-

Practice

One

s

Tens


Mat

h Pr

actic

e

MP 1 Make sense of problems and persevere in solving them

Ask students how they would start this problem. Be sure that they line up the numbers. Have

them then talk out each step.

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Web Practice


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51 6 8 - 3 6

A 94

B 32

C 31


51 6 8 - 3 6

A 94

B 32


Ans

wer

B

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52 3 6 - 1 5


52 3 6 - 1 5


Ans

wer

21




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53 4 6 - 2 3


53 4 6 - 2 3


Ans

wer

13

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54 35 - 21 =


54 35 - 21 =


Ans

wer

14

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Lab: Subtraction Spin· Assemble spinners by cutting out the two circles and arrows. Attach the arrow to the center of the spinner with a brad.· Have students work with a partner.· Student 1 spins spinner A and write the number on the top line of the subtraction sentence. Repeat with spinner B and write the number under the first number.· Student 1 solves the subtraction sentence on the paper while student 2 uses a calculator to check the answer. If student 1 is incorrect, have the students work together to find the mistake.· Switch rolls and repeat.


Click here for a more information

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Word Problems


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There are 3 different types of subtraction problems

1. Take away

2. Comparison

3. Part/Part/Whole

We solve all three by lining up the numbers on

top of each other and subtracting.

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Take Away

Take away problems ask us to find how many are left. We start with a group of objects and take some away.

There are 26 red birds on a fence and 14 fly away.

How many are left?

26 - 14 = ?

xxxxxx xxxxx xxx

Slide 194 / 225

Part/Part/Whole

In part/part/whole problems,

we are looking for the missing part.

Jim has 43 Skittles.

12 of them are red.

How many are not red?

Whole

Part Part

4312 ?43 - 12 = ?

Slide 195 / 225

Comparison

Comparison problems ask us to find the difference between two amounts.

How many more? How many less? How much bigger? How much smaller?

Jim has 45 pencils. Jess has 67 pencils. How many more pencils does Jess have?

67 - 45 = ?

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Sometimes subtraction word problems require multiple steps.It is helpful to underline the 2 parts in different colors.

Joe went to the store and bought 12 bananas and 21 apples. His sister ate 10 pieces of fruit. How

many apples and bananas are left?

Word Problems

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Step 1: How many pieces of fruit did Joe buy in all?

12 + 21 = ______?

In order to find how many are left, we need to first find out how many he started with.

Word Problem




Step 1: How many pieces of fruit did Joe buy in all?

12 + 21 = ______?

In order to find how many are left, we need to first find out how many he started with.

Word Problem

Teac

her N

otes


Click on the ? to show the addition problem.

Slide 198 / 225

Joe went to the store and bought 12 bananas and 21 apples. His sister ate 10 pieces of fruit. How many

apples and bananas are left?

Step 2: How many pieces are left after his sister ate some?

33 - 10 = ______?

Word Problem

Slide 199 / 225

What type of problem is it?

Bob went to the grocery store. He bought 18 hot dogs and 29

hamburgers for a party. How many more hamburgers did he

buy than hot dogs?



Bob went to the grocery store. He bought 18 hot dogs and 29

hamburgers for a party. How many more hamburgers did he

buy than hot dogs?

Teac

her N

otes


Work through the problems with the students. Take time

to discuss what type of problem it is. Have students

work on the problems at their desks while another

student completes it on the board.

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Mom bought 36 items at the store. 23 of the items were frozen. How

many items were not frozen?

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Dad baked 24 cookies. Jim ate 13 of the cookies. His sister ate the rest. How many did his sister eat?

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Billy had 16 puppies for sale. 14 of them were bought. How many are left?

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There are 37 peanut butter cups in a bag. John ate 11 and Betty ate 14. How many are left?

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Jess weighs 68 pounds. Her sister weighs 34 pounds. How much less

does her sister weigh?

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55 Which type of subtraction story is this?

Jen had 27 nail polishes. 12 of them broke. How many are left?

A Part/Part/Whole

B Take Away

C Comparison

(Answer) / 225

55 Which type of subtraction story is this?

Jen had 27 nail polishes. 12 of them broke. How many are left?

A Part/Part/Whole

B Take Away

C Comparison[This object is a pull tab]

Ans

wer

B

Slide 206 / 225

56 Which two numbers would you add first?

The pet store has 11 gray kittens and 26 white kittens. 14 kittens were bought. How many kittens are left?

A 11

B 26

C 14


56 Which two numbers would you add first?

The pet store has 11 gray kittens and 26 white kittens. 14 kittens were bought. How many kittens are left?

A 11

B 26

C 14


Ans

wer

A and B

Slide 207 / 225

57 Ron has 67 dollars. He went to the store and spent 24 dollars. How much does he have left?

A 91

B 34

C 43


57 Ron has 67 dollars. He went to the store and spent 24 dollars. How much does he have left?

A 91

B 34


Ans

wer

C

Slide 208 / 225

58 The computer lab has 35 computers. A class comes and uses 22 computers. How many computers are not being used?

(Answer) / 225

58 The computer lab has 35 computers. A class comes and uses 22 computers. How many computers are not being used?


Ans

wer

13

Slide 209 / 225

59 Bob has 57 flowers in his garden. Chris has 45 flowers in his garden. How many more flowers does Bob have?

QUIZ


59 Bob has 57 flowers in his garden. Chris has 45 flowers in his garden. How many more flowers does Bob have?

QUIZ


Ans

wer

12

Slide 210 / 225

Lab: Subtraction Around the RoomDirections:

· Print out one copy of the cards and laminate them.· Cut out the cards and tape them around the room.· Students move around the room looking for the subtraction problems.· Students write and solve the subtraction sentence in the box numbered with the same number as the card.


Click here for more information

Slide 211 / 225 Slide 212 / 225

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http://njctl.org/courses/math/1st-grade/2nd-digit-subtraction/subtraction-around-the-room/

/ 225

Extra Word Problems


Slide 214 / 225

Fruit Stand Prices

40 40 90 70 20

Use the above prices for each type of fruit to solve the following problems.

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You have 55 cents.You buy an apple.How many cents do you have left?

55- 40

Fruit Stand Prices

40 40 90 70 20

Slide 216 / 225

You have 72 cents.You buy a pear.How many cents do you have left?

72- 40

Fruit Stand Prices

40 40 90 70 20

Slide 217 / 225

You have 63 cents.You buy a strawberry.How many cents do you have left?

63- 20

Fruit Stand Prices

40 40 90 70 20

Slide 218 / 225

You have 63 cents.You buy 2 strawberries.How many cents do you have left?

63-

Fruit Stand Prices

40 40 90 70 20

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(Answer) / 225

You have 63 cents.You buy 2 strawberries.How many cents do you have left?

63-

Fruit Stand Prices

40 40 90 70 20Te

ache

r Not

es


Make sure students notice that they are buying 2

strawberries in this problem. Since it is a two step problem it is important to walk through

it with them the first time.

Slide 219 / 225

You have 90 cents.You buy a pineapple.How many cents do you have left?

Fruit Stand Prices

40 40 90 70 20

Slide 220 / 225

60 You have 80 cents. You buy a tomato. How many cents do you have left?

Farm Stand Prices

70 50 60 40 10


60 You have 80 cents. You buy a tomato. How many cents do you have left?

Farm Stand Prices

70 50 60 40 10


Ans

wer

30

Slide 221 / 225

61 You have 70 cents. You buy a green pepper. How many cents do you have left?

Farm Stand Prices

70 50 60 40 10


61 You have 70 cents. You buy a green pepper. How many cents do you have left?

Farm Stand Prices

70 50 60 40 10


Ans

wer

30

/ 225

62 You have 70 cents. You buy a potato. How many cents do you have left?

Farm Stand Prices

70 50 60 40 10


62 You have 70 cents. You buy a potato. How many cents do you have left?

Farm Stand Prices

70 50 60 40 10


Ans

wer

0

Slide 223 / 225

63 You have 90 cents. You buy an ear of corn. How many cents do you have left?

Farm Stand Prices

70 50 60 40 10


63 You have 90 cents. You buy an ear of corn. How many cents do you have left?

Farm Stand Prices

70 50 60 40 10[This object is a pull tab]

Ans

wer

30

Slide 224 / 225

64 You have 90 cents. You buy 4 carrots. How many cents do you have left?

Farm Stand Prices

70 50 60 40 10

Slide 225 / 225

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