# Into Math Grade 1 Module 4 Lesson 4 Answer Key Use Addition to Check Subtraction

We included HMH Into Math Grade 1 Answer Key PDF Module 4 Lesson 4 Use Addition to Check Subtraction to make students experts in learning maths.

## HMH Into Math Grade 1 Module 4 Lesson 4 Answer Key Use Addition to Check Subtraction

I Can use a related addition fact to check the answer to a subtraction problem.

Martina has 11 fruits. 8 are mangos. The rest of the fruits are pineapples. How can you use related facts to find how many pineapples she has?   Explanation:
Martina has 11 fruits
8 are mangos
The rest of the fruits are pineapples
I drew to show the difference
11 – 8 = 3
The related equations are
11 – 3 = 8
8 + 3 = 11
3 + 8 = 11
So, Martina has 3 pineapples.

Read the problem aloud. Have pairs of children choose tools to show the problem as addition and subtraction, Children should write related addition and subtraction facts that can be used to solve the problem.

Build Understanding

13 children play sports after school. 6 of them play soccer. The rest play basketball. How many children play basketball after school?

A. How can you show the problem? B. How can you write a subtraction equation to model the problem?
____ – ___ = ____
C. ___ children play basketball after school.
D. How can you write an addition equation to check your subtraction?
___ + __ = ___ Explanation:
13 children play sports after school
6 of them play soccer
I drew to show the difference
13 – 6 = 7
7 children play basketball after school
The addition equation to check is 6 + 7 = 13.

Turn and Talk How does adding help you check subtraction?

Step It Out

1. 17 animals are in the park. 8 are squirrels. The rest are skunks. How many skunks are in the park? A. Subtract to solve. Use any strategy.
17 – 8 = ___
B. Write a related addition fact to check your subtraction.
THINK: Use the same 3 numbers.
___ + ___ = ___
C. There are ____ skunks in the park.
17 – 8 = 9
8 + 9 = 17
There are 9 skunks in the park

Explanation:
17 – 8 =
Make 10:
17 – 8
= 17 – 7 – 1
= 10 – 1
= 9
17 – 8 = 9
The related fact is 8 + 9 = 17
So, there are 9 skunks in the park.

Check Understanding Math Board

Question 1.
Benny sees 16 dogs. 8 of them are young. The rest ape old. How many dogs are old?
16 – 8 = ___
___ + ___ = ___
___ old dogs
16 – 8 = 8
8 + 8 = 16
8 old dogs

Explanation:
Benny sees 16 dogs
8 of them are young
The rest are old
16 – 8 =
Use doubles fact:
8 + 8 = 16
So, 16 – 8 = 8
There are 8 old dogs.
8 + 8 = 16
So, the difference of 16 and 8 is 8.

Question 2.
13 – 9 = ___
___ + ___ = ____
13 – 9 = 4
9 + 4= 13

Explanation:
Make 10:
13 – 9
= 13 -3 – 6
= 10 – 6
= 4
13 – 9 = 4
So, 9+ 4 = 13
9 + 4 = 13
So, the difference of 13 and 9 is 4.

Question 3.
11 – 5 = ___
___ + ___ = ___
11 – 5 = 6
5 + 6 = 11

Explanation:
Make 10:
11 – 5
= 11 – 1 – 4
= 10 – 4
= 6
11 – 5 = 6
So, 5 + 6 = 11
5 + 6 = 11
So, the difference of 11 and 5 is 6.

Question 4.
Open Ended Dan builds 10 sandcastles. Some are small, and some are big. How many big sandcastles could he build? 10 – ___ = ___
___ + ___ = ____ ____ big sandcastles
10 – 6 = 4
6 + 4 = 10
4 big sandcastles

Explanation:
Dan builds 10 sandcastles
Some are small, and some are big
Think 6 are small
Subtract 6 from 10 to find the big castles
10 – 6 = 4
So, 4 sand castles are big.

Question 5.
Model with Mathematics Melissa has 16 crayons. 7 are blue. The rest are red. How many crayons are red?
16 – 7 = ___
___ + ___ = ___ ___ red crayons
16 – 7 = 9
7 + 9 = 16
9 red crayons

Explanation:
Melissa has 16 crayons
7 are blue
The rest are red
16 – 7 =
Make ten:
16 – 7
= 16 – 6 – 1
= 10 – 1
= 9
So, 16 – 7 = 9
There are 9 red crayons.

Question 6.
12 – 4 = ___
___ + ___ = ___
12 – 4 = 8
8 + 4 = 12

Explanation:
12 – 4 =
Make 10:
12 – 4
= 12 – 2 – 2
= 10 – 2
= 8
12 – 4 = 8
8 + 4 = 12
So, the difference of 12 and 4 is 8.

Question 7.
11 – 8 = ___
___ + ___ = ___
11 – 8 = 3
8 + 3 = 11

Explanation:
11 – 8 =
Make 10:
11 – 1 – 7
= 10 – 7
= 3
So, 11 – 8  = 3