All the solutions provided in **McGraw Hill My Math Grade 1 Answer Key PDF Chapter 4 Lesson 1 Count Back 1, 2, or 3 **will give you a clear idea of the concepts.

## McGraw-Hill My Math Grade 1 Answer Key Chapter 4 Lesson 1 Count Back 1, 2, or 3

**Explore and Explain**

Answer:

Explanation:

There are 5 squirrels playing

3 of the squirrels run away

Count back to subtract

Start with 5

Count back 3

4, 3, 2

So, 5 – 3 = 2

Therefore, 2 squirrels are still playing.

**Teacher Directions:** Use to model. There are 5 squirrels playing. 3 of the squirrels run away. How many squirrels are still playing? Write the number.

**See and Show**

You can count back to subtract. Start with 6. Count back 2.

**Helpful Hint**

Count back and take away cubes from the train. Write the numbers.

**Count back to subtract. Use to help.**

Question 1.

Start with 8.

Answer:

Explanation:

Count back to subtract

Start with 8

Count back 3

7, 6, 5

The difference of 8 and 3 is 5

So, 8 – 3 = 5.

Question 2.

7, ____

7 – 1 = ____

Answer:

Explanation:

Count back to subtract

Start with 7

Count back 1

6

The difference of 7 and 1 is 6

So, 7 – 1 = 6.

Question 3.

4, ___, ____

4 – 2 = ____

Answer:

Explanation:

Count back to subtract

Start with 4

Count back 2

3, 2

The difference of 4 and 2 is 2

So, 4 – 2 = 2.

Question 4.

12, ____, ____

12 – 2 = ____

Answer:

Explanation:

Count back to subtract

Start with 12

Count back 2

11, 10

The difference of 12 and 2 is 10

SO, 12 – 2 = 10.

Question 5.

10, ____, ___, ____

10 – 3 = ____

Answer:

Explanation:

Count back to subtract

Start with 10

Count back 3

9, 8, 7

The difference of 10 and 3 is 7

So, 10 – 3 = 7.

**Talk Math** How do you count back to find 7 – 2?

Answer:

7- 2 = 5

Explanation:

Count back to subtract

Start with 7

Count back 2

6, 5

The difference of 7 and 2 is 5

So, 7 – 2 = 5.

**On My Own**

**Count back to subtract, Use to help.**

Question 6.

11 – 2 = ____

Answer:

Explanation:

Count back to subtract

Start with 11

Count back 2

10, 9

The difference of 11and 2 is 9

So, 11 – 2 = 9.

Question 7.

12 – 3 = ___

Answer:

Explanation:

Count back to subtract

Start with 12

Count back 3

11, 10, 9

The difference of 12 and 3 is 9

So, 12 – 3 = 9.

Question 8.

3 – 2 = ___

Answer:

Explanation:

Count back to subtract

Start with 3

Count back 2

2, 1

The difference of 3 and 2 is 1

So, 3 – 2 = 1.

Question 9.

10 – 3 = ____

Answer:

Explanation:

Count back to subtract

Start with 10

Count back 3

9, 8, 7

The difference of 10 and 3 is 7

So, 10 -3 = 7.

Question 1o.

9 – 3 = ___

Answer:

Explanation:

Count back to subtract

Start with 9

Count back 3

8, 7, 6

The difference of 9 and 3 is 6

So, 9 – 3 = 6.

Question 11.

4 – 1 = ____

Answer:

Explanation:

Count back to subtract

Start with 4

Count back 1

3

The difference of 4 and 1 is 3

So, 4 – 1 = 3.

Question 12.

6 – 1 = ____

Answer:

Explanation:

Count back to subtract

Start with 6

Count back 1

5

The difference of 6 and 1 is 5

So, 6 – 1 = 5.

Question 13.

11 – 3 = ____

Answer:

Explanation:

Count back to subtract

Start with 11

Count back 3

10, 9, 8

The difference of 11 and 3 is 8

So, 11 – 3 = 8.

Question 14.

7 – 3 = ___

Answer:

Explanation:

Count back to subtract

Start with 7

Count back 3

6, 5, 4

The difference of 9 and 3 is 4

So, 7 – 3 = 4.

Question 15.

9 – 2 = ____

Answer:

Explanation:

Count back to subtract

Start with 9

Count back 2

8, 7

The difference of 9 and 2 is 7

So, 9 – 2 = 7.

Question 16.

Answer:

Explanation:

The difference of 10 and 2 is 8.

Question 17.

Answer:

Explanation:

The difference of 9 and 2 is 7.

Question 18.

Answer:

Explanation:

The difference of 8 and 1 is 7.

Question 19.

Answer:

Explanation:

The difference of 12 and 2 is 10.

Question 20.

Answer:

Explanation:

The difference of 10 and 1 is 9.

Question 21.

Answer:

Explanation:

The difference of 5 and 3 is 2.

**Problem Solving**

**Write a subtraction number sentence to solve.**

Question 22.

There are 5 pelicans sitting on a rock. 1 of them flies away. How many pelicans are still sitting on the rock?

_____ – ____ = ____ pelicans

Answer:

Explanation:

There are 5 pelicans sitting on a rock

1 of them flies away

Count back to subtract

Start with 5

Count back 1

4

The difference of 5 and 1 is 4

So, 5 – 1 = 4

4 pelicans are still sitting on the rock.

Question 23.

There are 11 boats at the dock. 3 of the boats leave. How many boats are still at the dock?

____ – ____ = ____ boats

Answer:

Explanation:

There are 11 boats at the dock

3 of the boats leave

Count back to subtract

Start with 11

Count back 3

10, 9, 8

The difference of 11 and 3 is 8

So, 11 – 3 = 8

8 boats are still at the dock.

**Write Math** How do you count back to find 11 – 2? Explain.

_______________________

_______________________

_______________________

_______________________

Answer:

Count back to subtract

Start with 11

Count back 2

10, 9

So, 11 – 2 = 9.

### McGraw Hill My Math Grade 1 Chapter 4 Lesson 1 My Homework Answer Key

**Practice**

**Count back to subtract.**

Question 1.

7, ____, _____

7 – 2 = _____

Answer:

Explanation:

Count back to subtract

Start with 7

Count back 2

6, 5

The difference of 7 and 2 is 5

So, 7 – 2 = 5.

Question 2.

9, ____, ____, ____

9 – 3 = ____

Answer:

Explanation:

Count back to subtract

Start with 9

Count back 3

8, 7, 6

The difference of 9 and 3 is 6

So, 9 – 3 = 6.

Question 3.

12, ___, ___, ____

12 – 3 = ____

Answer:

Explanation:

Count back to subtract

Start with 12

Count back 3

11, 10, 9

The difference of 12 and 3 is 9

So, 12 – 3 = 9.

Question 4.

11, ___, ____

11 – 2 = ___

Answer:

Explanation:

Count back to subtract

Start with 11

Count back 2

10, 9

The difference of 11 and 2 is 9

So, 11 – 2 = 9.

**Count back to subtract.**

Question 5.

11 – 3 = ____

Answer:

Explanation:

Count back to subtract

Start with 11

Count back 3

10, 9, 8

The difference of 11 and 3 is 8

So, 11 – 3 = 8.

Question 6.

8 – 1 = ____

Answer:

Explanation:

Count back to subtract

Start with 8

Count back 1

7

The difference of 8 and 1 is 7

So, 8 – 1 = .

Question 7.

5 – 2 = ___

Answer:

Explanation:

Count back to subtract

Start with 5

Count back 2

4, 3

The difference of 5 and 2 is 3

So, 5 – 2 = 3.

Question 8.

12 – 2 = ____

Answer:

Explanation:

Count back to subtract

Start with 12

Count back 2

11, 10

The difference of 12 and 2 is 10

So, 12 – 2 = 10.

Question 9.

10 – 3 = ____

Answer:

Explanation:

Count back to subtract

Start with 10

Count back 3

9, 8, 7

The difference of 10 and 3 is 7

So, 10 – 3 = 7.

Question 10.

9 – 2 = ____

Answer:

Explanation:

Count back to subtract

Start with 9

Count back 2

8, 7

The difference of 9 and 2 is 7

So, 9 – 2 = 7.

Question 11.

Answer:

Explanation:

The difference of 8 and 3 is 5.

Question 12.

Answer:

Explanation:

The difference of 12 and 1 is 11.

Question 13.

Answer:

Explanation:

The difference of 11 and 2 is 9.

Question 14.

London had 9 masks. He lost 3 of them. How many masks does he have left?

____ masks

Answer:

Explanation:

London had 9 masks

He lost 3 of them

Start at 9

Count back 3

8, 7, 6

I reach at 6

So, London is left with 6 marks.

**Vocabulary Check**

**Circle the correct answer.**

count back count on

Question 15.

Start at the number 6 and ____ by 2 to get the difference of 4.

Answer:

Start at the number 6 and count back by 2 to get the difference of 4.

**Math at Home** Write 12 – 3 = ___. Have your child write the answer and explain how to count back to solve the problem.

Answer:

12- 3 = 9

Explanation:

Count back to subtract

Start with 12

Count back 3

11, 10, 9

So, 12 – 3 = 9.