We included HMH 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.

___ – ___ = ___
5 + 9 = 14
14 – 5 = ___
So, 5 + __ = 14.
14 – 5 = 9
So, 5 + 9 = 14
C. ___ fish are green.
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.

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.

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
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.

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.
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.
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.

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
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
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
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
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
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