We included HMH Into Math Grade 1 Answer Key PDF Module 2 Lesson 2 Count Back to make students experts in learning maths.
HMH Into Math Grade 1 Module 2 Lesson 2 Answer Key Count Back
I Can count back to solve a subtraction problem.
Spark Your Learning
Viktoria makes 7 picture frames. She gives 2 to her friend. How many picture frames does she have now?
How can counting help you solve the problem?
Answer:
Explanation:
Viktoria makes 7 picture frames
She gives 2 to her friend.
I drew counters to show
7 – 2 = 5
So, she have 5 picture frames now.
Read the problem to children. Allow small groups to choose tools and work together to show how to count to solve the problem.
Build Understanding
Dina has 9 balloons. Then I balloon floats away. How many balloons does she have now?
How can you count back to show the problem?
A. What number do you start on? ___
B. How can you show how to count back 1?
Answer:
C. How can you write an equation to show the problem?
___ – ___ = ___
D. Dina has ___ balloons now.
Explanation:
Dina has 9 balloons
Then I balloon floats away
I start on number 9
I counted 1 back
9 – 1 = 8
So, Dina has 8 balloons now.
Connect to Vocabulary
count back:
Start at 5.
Count back 2.
5 – 2 = 3
Turn and Talk How do you count back 0?
Answer:
Count back 0 is nothing to count back.
The answer is the number we started with.
A kangaroo is on step 6 and takes 2 jumps down. What step is the kangaroo on now?
A. How can you use the picture to show how to count back?
Answer:
B. How can you write an equation to show the problem?
___ – ___ = ____
C. The kangaroo is on step ___ now.
Explanation:
A kangaroo is on step 6 and takes 2 jumps down
Start at 6
Count back 2.
6 – 2 = 4
So, the kangaroo is on 4th step now.
Turn and Talk How does counting back help you subtract?
Answer:
counting back helps us to reach the answer directly by counting backward.
Step It Out
1. Use a number line to count back to subtract.
8 – 3 = 
A. What number do you start on? ___
B. How many jumps back do you make? ___
Draw the jumps on the number line above.
C. What number do you land on? ___
D. So, 8 – 3 = ___.
Answer:
Explanation:
I started on the number 8
I made 3 jumps back
I drew the jumps on the number lines
So, 8 – 3 = 5.
Check Understanding Math Board
Count back to subtract.
Question 1.
Morgan has 5 toy trucks. He gives 2 toy trucks to a friend. How many toy trucks does he have now? Draw or write to explain.
5 – 2 = ___
___ toy trucks
Answer:
3 toy trucks
Explanation:
Morgan has 5 toy trucks
He gives 2 toy trucks to a friend
Start at 5
Count back 2
5 – 2 = 3
So, Morgan have 3 Toy tracks now.
Question 2.
10 – 1 = ___
Answer:
10 – 1 = 9
Explanation:
Start at 10
Count back 1
I reach at 9
So, 10 – 1 = 9.
Question 3.
4 – 3 = ___
Answer:
4 – 3 = 1
Explanation:
Start at 4
Count back 3
I reach at 1
So, 4 – 3 = 1.
Question 4.
6 – 2 = __
Answer:
6 – 2 = 4
Explanation:
Start at 6
Count back 2
I reach at 4
So, 6 – 2 = 4.
On Your Own
Count back to subtract.
Question 5.
There are 7 children on the bus. Then 3 children get off the bus. How many children are still on the bus?
___ – ___ = ____
___ children are still on the bus.
Answer:
7 – 3 = 4
3 children are still on the bus
Explanation:
There are 7 children on the bus
Then 3 children get off the bus
Start at 7
Count back 3
I reach at 4
7 – 3 = 4
So, 3 children are still on the bus.
Question 6.
Use Tools Jaden has 10 marbles. He gives 2 to Ana. How many marbles does Jaden have now? Draw jumps to show your thinking.
___ – ___ = ___
Jaden has ___ marbles now.
Answer:
Explanation:
Jaden has 10 marbles
He gives 2 to Ana
Start at 10
Count back 2
I reach at 8
So, 10 – 2 = 8
Therefore, Jaden has 8 marbles now.
Question 7.
10 – 3 = ___
Answer:
10 – 3 = 7
Explanation:
Start at 10
Count back 3
I reach at 7
So, 10 – 3 = 7.
Question 8.
7 – 1 = ___
Answer:
7 – 1 = 6
Explanation:
Start at 7
Count back 1
I reach at 6
So, 7 – 1 = 6.
Question 9.
3 – 3 = ___
Answer:
3 – 3 = 0
Explanation:
Start at 3
Count back 3
I reached at 0
So, 3 – 3 = 0.
Question 10.
6 – 3 = ___
Answer:
6 – 3 = 3
Explanation:
Start at 6
Count back 3
I reach at 3
So, 6 – 3 = 3.
Question 11.
9 – 3 = ___
Answer:
9 – 3 = 6
Explanation:
Start at 9
Count back 3
I reach at 6
So, 9 – 3 = 6.
Question 12.
11 – 2 = ___
Answer:
11 – 2 = 9
Explanation:
start at 11
Count back 2
I reach at 9
So, 11 – 2 = 9.
Question 13.
__ = 8 – 0
Answer:
8 – 0 = 8
Explanation:
Start at 8
Count back 0
I will be at 8
So, 8 – 0 = 8
Question 14.
___ = 3 – 1
Answer:
3 – 1 = 2
Explanation:
Start at 3
Count back 1
I reach at 2
So, 3 – 1 = 2.
On Your Own
Count back to subtract.
Question 15.
Model with Mathematics There are 12 books on a table. Cindy puts 3 of the books on a bookshelf. How many books are on the table now?
___ – ___ = ___
___ books
Answer:
12 – 3 = 9
9 books
Explanation:
There are 12 books on a table
Cindy puts 3 of the books on a bookshelf
Start at 12
Count back 3
I reach at 9
So, 12 – 3 = 9
Therefore, 9 books are on the table now.
Question 16.
Attend to Precision Draw to show how to count back to subtract 8 – 2.
Answer:
Explanation:
Start at 8
Count back 2
I reach at 6
So, 8 – 2 = 6.
Question 17.
Open Ended Choose a number. Count back 1. Write the equation.
___ – ___ = ___
Answer:
I chose the number 9
I start at 9
Count back 1
I reach at 8
So, 9 – 1 = 8.
I’m in a Learning Mindset!
Did using a number line help me understand how to count back to subtract? Explain.