We included HMH Into Math Grade 2 Answer Key PDF Module 1 Lesson 4 Develop Fluency with Subtraction Using Mental Strategies to make students experts in learning maths.
HMH Into Math Grade 2 Module 1 Lesson 4 Answer Key Develop Fluency with Subtraction Using Mental Strategies
I Can use related addition facts or count back to find differences.
Spark Your Learning
How can you represent the problem? Write a subtraction fact and a related addition fact for the problem.
Answer:
Explanation:
9 – 5 = 4
There are 4 sand castles left.
Read the following problem. Michele and a friend see 9 sandcastles at the beach. Then 5 sandcastles are there now? How many sandcastles are there now? Have children represent the problem and then write a subtraction fact and a related addition fact.
Build Understanding
Ned stacks 12 cans. There are 5 cans of peaches. The rest are cans of corn. How many cans of corn
does Ned stack?
A. How can you use tools to show the problem?
Answer:
B. What subtraction fact can you write to show the problem?
___ – ___ = 
Answer:
12 – 5 = 7
C. What related addition fact can help you solve the problem?
___ + ___ = ___
Answer:
5 + 7 = 12
D. Write the subtraction fact. Then solve.
___ – ___ = ___ ___ cans of corn
Answer:
12 – 5 = 7
7 cans of corn.
Turn and Talk How can the addition fact 9 + 2 = 11 help you find 11 – 9?
Step It Out
1. Mr. Smith makes 13 blueberry muffins and 7 corn muffins. How many fewer corn muffins than blueberry muffins does Mr. Smith make?
A. Write a subtraction fact to show the problem.
___ – ___ = 
Answer:
13 – 7 = 6
B. Use tools or draw to show the problem.
Answer:
C. Use a related addition fact to help you solve the problem. Write the missing addend.
7 + __ = 13
Answer:
7 + 6 = 13
D. Use the missing addend to write the subtraction fact.
___ – ___ = ____
Answer:
13 – 7 = 6
E. Solve.
___ fewer corn muffins
Answer:
13 – 7 = 6
6 fewer corn muffins.
Step It Out
2. At a picnic, there are 11 children. 3 children choose a granola bar as a snack. The rest of the children choose a fruit cup. How many children choose a fruit cup?
A. Start with 11.
B. Identify the number you are subtracting.
_____
C. Count back the same number of times as the number you are subtracting.
Count back 3. 11, ___, ___, ____
11, 8, 5, 2, 0
D. Write the difference. Solve.
11 – 3 = ____ _____ children
Answer:
Related fact: 8 + 3 = 11
11 – 3 = 8
8 children chose a fruit cup.
Check Understanding Math Board
Question 1.
Marie sees 15 fish in the river. There are 8 trout. The rest of the fish are catfish. How many catfish does Marie see? Write the subtraction fact. Then solve.
___ – ___ = ___
___ catfish
Answer:
15 – 8 = 7
7 catfish
Explanation:
15 – 8 = 7
Related fact: 7 + 8 = 15
So, Mari saw 7 catfishes.
Find the difference.
Question 2.
13 – 8 = ___
Answer:
5
Explanation:
13 – 8 = 5
Related fact: 8 + 5 = 13
The difference of 13 and 8 is 5.
Question 3.
___ = 12 – 3
Answer:
9
Explanation:
12 – 3 = 9
Related fact: 3 + 9 = 13
The difference of 12 and 3 is 9.
On Your Own
Draw to show the problem.
Question 4.
Reason There are 10 trees in a field. There are 6 cedar trees. The rest are oak trees. How many oak trees are there? Write a subtraction fact to solve.
___ – ___ = ___
___ oak trees
Answer:
10 – 6 = 4
4 oak trees
Explanation:
10 – 6 = 4
Related fact: 6 + 4 = 10
The difference of 10 and 6 is 4.
Question 5.
Construct Arguments There are 12 squirrels sitting in an oak tree. Then 9 squirrels leave the tree. How many squirrels are in the tree now? What strategy did you use to solve the problem? Explain.
Answer:
3
Explanation:
12 – 9 = 3
Related fact: 9 + 3 = 12
3 squirrels are in the tree now.
Question 6.
Open Ended Hank has 13 action figures. He gives some of his action figures to his sister. Decide how many action figures Hank will give to his sister.
Write four related facts to show your problem.
___ – ___ = ___ ___ + ___ = _____
___ – ___ = ___ ___ + ___ = _____
Answer:
13 – 3 = 10, 10 + 3 = 13
13 – 10 = 3, 3 + 10 = 13
Explanation:
I wrote the related facts of the numbers
Hank can give 3 action figures to his sister.
On Your Own
Attend to Precision Find the difference.
Question 7.
7 – 5 = __
Answer:
2
Explanation:
7 – 5 = 2
Related fact: 5 + 2 = 7
The difference of 7 and 5 is 2.
Question 8.
6 – 8 = ___
Answer:
2
Explanation:
6 – 8 = 2
Related fact: 2 + 6 = 8
The difference of 8 and 6 is 2.
Question 9.
___ = 6 – 3
Answer:
3
Explanation:
6 – 3 = 3
Related fact:
3 + 3 = 6
The difference of 6 and 3 is 3.
Question 10.
15 – 7 = ___
Answer:
8
Explanation:
15 – 7 = 8
Related fact: 7 + 8 = 15
The difference of 15 and 7 is 8.
Question 11.
___ = 9 – 5
Answer:
4
Explanation:
9 – 5 = 4
Related fact: 5 + 4 = 9
The difference of 9 and 5 is 4.
Question 12.
12 – 4 = ___
Answer:
8
Explanation:
12 – 4 = 8
Related fact: 8 + 4 = 12
The difference of 12 and 4 is 8.
Question 13.
___ = 8 – 6
Answer:
2
Explanation:
8 – 6 = 2
Related fact: 6 + 2 = 8
The difference of 8 and 6 is 2.
Question 14.
11 – 4 = ___
Answer:
8
Explanation:
11 – 4 = 8
Related fact: 8 + 4 = 11
The difference of 11 and 4 is 8.
Question 15.
6 – 0 = ___
Answer:
6
Explanation:
6
Explanation:
6 – 0 = 6
The difference of 6 and 0 is 6.
Question 16.
Joe counts lizards at a park. Laura counts 3 lizards at the park. How many more lizards does Joe count than Laura? Explain the strategy you used.
Answer:
I’m in a Learning Mindset!
What makes me curious about subtraction strategies?
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