We included **H****MH Into Math Grade 1 Answer Key**** PDF** **Module 4 Lesson 6 Solve for the Unknown Addend** to make students experts in learning maths.

## HMH Into Math Grade 1 Module 4 Lesson 6 Answer Key Solve for the Unknown Addend

I Can solve problems that have an unknown addend.

**Step It Out**

1. 5 fish are orange. The rest are green. There are 14 fish in all. How many fish are green?

5 + = 14

A. Write a related subtraction fact. Subtract the number of orange fish from the total number of fish.

___ – ___ = ___

Answer:

5 + 9 = 14

B. Use the subtraction fact to help you find the unknown addend.

14 – 5 = ___

So, 5 + __ = 14.

Answer:

14 – 5 = 9

So, 5 + 9 = 14

C. ___ fish are green.

Answer:

9 fishes are green.

Explanation:

5 fish are orange

The rest are green

There are 14 fish in all

The related subtraction fact that shown by the drawing is 14 – 5 = 9

So, 5 + 9 = 14

There are 9 green fishes.

**Step It Out**

2. Julia has 8 apples. The rest of her fruits are peaches. She has 17 fruits in all. How many peaches does Julia have?

A. Use addition to show the problem.

B. Write a related subtraction fact to solve.

___ – ___ = ____

So, 8 + __ = 17

C. Julia has peaches.

Answer:

Explanation:

Julia has 8 apples

The rest of her fruits are peaches

She has 17 fruits in all

The related subtraction fact that solves the problem is

17 – 8 = 9

So, 8 + 9 = 17

Julia has 9 peaches.

**Turn and Talk** Explain how a subtraction fact can help you find an unknown addend.

Answer:

We can use related facts to find the missing or unknown addend

For example if we have number 9 + _ = 17

We need to subtract 9 from 17 to find the missing addend

17 – 9 = 8 is the related subtraction equation

So, 9 + 8 = 17 is the subtraction equation.

**Check Understanding Math Board**

**Write a related subtraction fact to solve.**

Question 1.

8 pens are blue. The rest are red. There are 14 in all. How many pens are red?

8 + = 14

___ – ___ = ____

8 + ___ = 14

___ red pens

Answer:

8 + = 14

14 – 8 = 6

So, 8 + 6 = 14

6 pens are red.

Explanation:

8 pens are blue

The rest are red

There are 14 in all

The related subtraction fact that solves the problem is

14 – 8 = 6

So, 8 + 6 = 14

There are 6 red pens.

**On Your Own**

**Write a related subtraction fact to solve.**

Question 2.

**Reason** 5 cows are in a field. The rest are in a barn. There are 12 cows in all. How many cows are in the barn?

5 + = 12

___ – ___ = ___

5 + ___ = 12

___ cows are in the barn.

Explain your thinking.

Answer:

5 + = 12

12 – 5 = 7

5 + 7 = 12

7 cows are in the barn.

Explanation:

5 cows are in a field

The rest are in a barn

There are 12 cows in all

The related subtraction fact that solves the problem is

12 – 5 = 7

So, 5 + 7 = 12

There are 7 cows in the barn.

Question 3.

9 people vote at city hall. The rest of them vote at school. 15 people vote altogether. How many people vote at school?

9 + = 15

___ – ___ = ____

9 + ___ = 15

____ people vote at school.

Answer:

9 + = 15

15 – 9 = 6

9 + 6 = 15

6 people vote at school.

Explanation:

9 people vote at city hall

The rest of them vote at school

15 people vote altogether

The related subtraction fact that solves the problem is

15 – 9 = 6

So, 9 + 6 = 15

6 people vote at school.

**On Your Own**

**Write a related subtraction fact to solve.**

Question 4.

3 bears have hats. The rest have bows. There are 11 bears in all. How many bears have bows?

3 + = 11

___ – ___ = ____

3 + ___ = 11 ____ bears

Answer:

3 + = 11

11 – 3 = 8

3 + 8 = 11

8 bears have bows.

Explanation:

3 bears have hats

The rest have bows

There are 11 bears in all

The related subtraction fact that solves the problem is

11 – 3 = 8

So, 3 + 8 = 11

8 bears have bows.

Question 5.

**Reason** 9 dolls wear pants. The rest wear dresses. There are 18 dolls in all. How many dolls wear dresses?

___ – ___ = ___

9 + ___ = 18 __ dolls

Answer:

18 – 9 = 9

9 + 9 = 18

9 dolls wear dresses

Explanation:

9 dolls wear pants

The rest wear dresses

There are 18 dolls in all

The related subtraction fact that solves the problem is

18 – 9 = 9

So, 9 + 9 = 18

9 dolls wear dresses.

Question 6.

What is 8 + = 17?

___ – ___ = ___

8 + ___ = 17

Answer:

17 – 8 = 9

8 + 9 = 17

Explanation:

8 + = 17

The related subtraction fact that solves the problem is

17 – 8 = 9

So, 8 + 9 = 17.

Question 7.

What is 4 + = 12?

___ – ___ = ___

4 + ___ = 12

Answer:

12 – 4 = 8

4 + 8 = 12

Explanation:

4 + = 12

The related subtraction fact that solves the problem is

12- 4= 8

So, 4 + 8 = 12.

Question 8.

What is 7 + = 14?

___ – ___ = ___

7 + ___ = 14

Answer:

14 – 7 = 7

7 + 7 = 14

Explanation:

7 + = 14

The related subtraction fact that solves the problem is

14 – 7 = 14

So, 7 + 7 = 14.

Question 9.

What is 8 + = 15?

___ – ___ = ___

8 + ___ = 15

Answer:

15 – 8 = 7

8 + 7 = 15

Explanation:

8 + = 15

The related subtraction fact that solves the problem is

15 – 8 = 7

So, 8 + 7 = 15.