All the solutions provided in McGraw Hill My Math Grade 1 Answer Key PDF Chapter 4 Lesson 1 Count Back 1, 2, or 3 will give you a clear idea of the concepts.
McGraw-Hill My Math Grade 1 Answer Key Chapter 4 Lesson 1 Count Back 1, 2, or 3
Explore and Explain
Answer:
Explanation:
There are 5 squirrels playing
3 of the squirrels run away
Count back to subtract
Start with 5
Count back 3
4, 3, 2
So, 5 – 3 = 2
Therefore, 2 squirrels are still playing.
Teacher Directions: Use 
to model. There are 5 squirrels playing. 3 of the squirrels run away. How many squirrels are still playing? Write the number.
See and Show
You can count back to subtract. Start with 6. Count back 2.
Helpful Hint
Count back and take away cubes from the train. Write the numbers.
Count back to subtract. Use 
to help.
Question 1.
Start with 8.
Answer:
Explanation:
Count back to subtract
Start with 8
Count back 3
7, 6, 5
The difference of 8 and 3 is 5
So, 8 – 3 = 5.
Question 2.
7, ____
7 – 1 = ____
Answer:
Explanation:
Count back to subtract
Start with 7
Count back 1
6
The difference of 7 and 1 is 6
So, 7 – 1 = 6.
Question 3.
4, ___, ____
4 – 2 = ____
Answer:
Explanation:
Count back to subtract
Start with 4
Count back 2
3, 2
The difference of 4 and 2 is 2
So, 4 – 2 = 2.
Question 4.
12, ____, ____
12 – 2 = ____
Answer:
Explanation:
Count back to subtract
Start with 12
Count back 2
11, 10
The difference of 12 and 2 is 10
SO, 12 – 2 = 10.
Question 5.
10, ____, ___, ____
10 – 3 = ____
Answer:
Explanation:
Count back to subtract
Start with 10
Count back 3
9, 8, 7
The difference of 10 and 3 is 7
So, 10 – 3 = 7.
Talk Math How do you count back to find 7 – 2?
Answer:
7- 2 = 5
Explanation:
Count back to subtract
Start with 7
Count back 2
6, 5
The difference of 7 and 2 is 5
So, 7 – 2 = 5.
On My Own
Count back to subtract, Use 
to help.
Question 6.
11 – 2 = ____
Answer:
Explanation:
Count back to subtract
Start with 11
Count back 2
10, 9
The difference of 11and 2 is 9
So, 11 – 2 = 9.
Question 7.
12 – 3 = ___
Answer:
Explanation:
Count back to subtract
Start with 12
Count back 3
11, 10, 9
The difference of 12 and 3 is 9
So, 12 – 3 = 9.
Question 8.
3 – 2 = ___
Answer:
Explanation:
Count back to subtract
Start with 3
Count back 2
2, 1
The difference of 3 and 2 is 1
So, 3 – 2 = 1.
Question 9.
10 – 3 = ____
Answer:
Explanation:
Count back to subtract
Start with 10
Count back 3
9, 8, 7
The difference of 10 and 3 is 7
So, 10 -3 = 7.
Question 1o.
9 – 3 = ___
Answer:
Explanation:
Count back to subtract
Start with 9
Count back 3
8, 7, 6
The difference of 9 and 3 is 6
So, 9 – 3 = 6.
Question 11.
4 – 1 = ____
Answer:
Explanation:
Count back to subtract
Start with 4
Count back 1
3
The difference of 4 and 1 is 3
So, 4 – 1 = 3.
Question 12.
6 – 1 = ____
Answer:
Explanation:
Count back to subtract
Start with 6
Count back 1
5
The difference of 6 and 1 is 5
So, 6 – 1 = 5.
Question 13.
11 – 3 = ____
Answer:
Explanation:
Count back to subtract
Start with 11
Count back 3
10, 9, 8
The difference of 11 and 3 is 8
So, 11 – 3 = 8.
Question 14.
7 – 3 = ___
Answer:
Explanation:
Count back to subtract
Start with 7
Count back 3
6, 5, 4
The difference of 9 and 3 is 4
So, 7 – 3 = 4.
Question 15.
9 – 2 = ____
Answer:
Explanation:
Count back to subtract
Start with 9
Count back 2
8, 7
The difference of 9 and 2 is 7
So, 9 – 2 = 7.
Question 16.
Answer:
Explanation:
The difference of 10 and 2 is 8.
Question 17.
Answer:
Explanation:
The difference of 9 and 2 is 7.
Question 18.
Answer:
Explanation:
The difference of 8 and 1 is 7.
Question 19.
Answer:
Explanation:
The difference of 12 and 2 is 10.
Question 20.
Answer:
Explanation:
The difference of 10 and 1 is 9.
Question 21.
Answer:
Explanation:
The difference of 5 and 3 is 2.
Problem Solving
Write a subtraction number sentence to solve.
Question 22.
There are 5 pelicans sitting on a rock. 1 of them flies away. How many pelicans are still sitting on the rock?
_____ – ____ = ____ pelicans
Answer:
Explanation:
There are 5 pelicans sitting on a rock
1 of them flies away
Count back to subtract
Start with 5
Count back 1
4
The difference of 5 and 1 is 4
So, 5 – 1 = 4
4 pelicans are still sitting on the rock.
Question 23.
There are 11 boats at the dock. 3 of the boats leave. How many boats are still at the dock?
____ – ____ = ____ boats
Answer:
Explanation:
There are 11 boats at the dock
3 of the boats leave
Count back to subtract
Start with 11
Count back 3
10, 9, 8
The difference of 11 and 3 is 8
So, 11 – 3 = 8
8 boats are still at the dock.
Write Math How do you count back to find 11 – 2? Explain.
_______________________
_______________________
_______________________
_______________________
Answer:
Count back to subtract
Start with 11
Count back 2
10, 9
So, 11 – 2 = 9.
McGraw Hill My Math Grade 1 Chapter 4 Lesson 1 My Homework Answer Key
Practice
Count back to subtract.
Question 1.
7, ____, _____
7 – 2 = _____
Answer:
Explanation:
Count back to subtract
Start with 7
Count back 2
6, 5
The difference of 7 and 2 is 5
So, 7 – 2 = 5.
Question 2.
9, ____, ____, ____
9 – 3 = ____
Answer:
Explanation:
Count back to subtract
Start with 9
Count back 3
8, 7, 6
The difference of 9 and 3 is 6
So, 9 – 3 = 6.
Question 3.
12, ___, ___, ____
12 – 3 = ____
Answer:
Explanation:
Count back to subtract
Start with 12
Count back 3
11, 10, 9
The difference of 12 and 3 is 9
So, 12 – 3 = 9.
Question 4.
11, ___, ____
11 – 2 = ___
Answer:
Explanation:
Count back to subtract
Start with 11
Count back 2
10, 9
The difference of 11 and 2 is 9
So, 11 – 2 = 9.
Count back to subtract.
Question 5.
11 – 3 = ____
Answer:
Explanation:
Count back to subtract
Start with 11
Count back 3
10, 9, 8
The difference of 11 and 3 is 8
So, 11 – 3 = 8.
Question 6.
8 – 1 = ____
Answer:
Explanation:
Count back to subtract
Start with 8
Count back 1
7
The difference of 8 and 1 is 7
So, 8 – 1 = .
Question 7.
5 – 2 = ___
Answer:
Explanation:
Count back to subtract
Start with 5
Count back 2
4, 3
The difference of 5 and 2 is 3
So, 5 – 2 = 3.
Question 8.
12 – 2 = ____
Answer:
Explanation:
Count back to subtract
Start with 12
Count back 2
11, 10
The difference of 12 and 2 is 10
So, 12 – 2 = 10.
Question 9.
10 – 3 = ____
Answer:
Explanation:
Count back to subtract
Start with 10
Count back 3
9, 8, 7
The difference of 10 and 3 is 7
So, 10 – 3 = 7.
Question 10.
9 – 2 = ____
Answer:
Explanation:
Count back to subtract
Start with 9
Count back 2
8, 7
The difference of 9 and 2 is 7
So, 9 – 2 = 7.
Question 11.
Answer:
Explanation:
The difference of 8 and 3 is 5.
Question 12.
Answer:
Explanation:
The difference of 12 and 1 is 11.
Question 13.
Answer:
Explanation:
The difference of 11 and 2 is 9.
Question 14.
London had 9 masks. He lost 3 of them. How many masks does he have left?
____ masks
Answer:
Explanation:
London had 9 masks
He lost 3 of them
Start at 9
Count back 3
8, 7, 6
I reach at 6
So, London is left with 6 marks.
Vocabulary Check
Circle the correct answer.
count back count on
Question 15.
Start at the number 6 and ____ by 2 to get the difference of 4.
Answer:
Start at the number 6 and count back by 2 to get the difference of 4.
Math at Home Write 12 – 3 = ___. Have your child write the answer and explain how to count back to solve the problem.
Answer:
12- 3 = 9
Explanation:
Count back to subtract
Start with 12
Count back 3
11, 10, 9
So, 12 – 3 = 9.