Introduction:
Count Back to Subtract.
We can use the number line to help to count back to subtract.
Example 1:
5 – 3= ____.
If I start at 5 and count back 3, I end at 2.
![count back 3](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/count-back-3.png)
5,4,3, 2
5 – 3 = 2
Example 2:
7 – 0 = ______.
When we subtract 0,
![Count Back](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/count-back-1024x194.png)
If I start at 7 and don’t count back any, I stay at 7.
7 – 0 = 7
Count Back to Subtract Examples:
Example 1:
Count back to complete subtraction facts.
Sol:
Start at 8.
When we subtract 3 by counting back 3,
![counting back 3](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/counting-back-3-1024x203.png)
8, 7, 6, 5
End at 5.
So, 8 – 3 = 5
Example 2:
Diana had 7 toffees. She gave 5 toffees to her friend. How many toffees left with her?
![5 toffees](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/5-toffees.png)
Sol:
Total number of toffees with Diana = 7
Number of toffees she gave to her friend = 5
The number of toffees left with Diana = 7 – 5
Start at 7 and count back 5.
![count back 5](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/count-back-5.png)
7 – 5 = 2
So, 2 toffees left with Diana.
Example 3:
There were 6 boats tied up. 4 of the boats sailed away. How many were left?
![boats sailed away](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/boats-sailed-away.png)
Sol:
Total number of boats tied up = 6
Number of boats sailed away = 4
The number of boats left = 6 – 4
Start at 6 and count back 4.
![count back 4](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/count-back-4.png)
6 – 4 = 2
So, 2 boats were left.
Exercise
- Count back to complete subtraction fact.
![Subraction Fact](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/Subraction-Fact-1024x194.png)
![Subraction Fact](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/Subraction-Fact-1.png)
2. Count back to subtract using the number line.
![Number Line](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/Number-Line-7-1024x306.png)
3. Subtract.
![Subraction](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/Subraction.png)
4. With the help of number line 7 – 4 = ____.
![Number line](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/Number-Line-8-1024x258.png)
5. Select the correct one.
10 – 5 = ____
![Choose the correct one](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/Choose-Correct-One-505x1024.png)
6. Count back to complete the subtraction fact 8 – 6 = ?
7. Tom sees 10 birds in a farm. He scares 6 of them and then they flew away. How many left?
![Bird](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/Bird-1024x683.jpg)
8. Leo has 4 mints. He eats 2 mints. How many mints does Leo have now?
![4 Toffees](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/4-toffee-858x1024.png)
9.There are 10 students in Grade 1. 6 of them are girls. How many boys are there in Grade 1?
![Grade 1](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/Grade-1-1024x996.png)
10. Find the value if we take away 1 from 3.
![1 from 3](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/1-From-3-1024x286.png)
Concept Map:
![Concept Map](https://www.turito.com/learn-internal/wp-content/uploads/2023/07/Concept-Map-4-1024x520.png)
What We Have Learned
- Count back to subtract
- Subtraction with the help of a number line
- Count back to solve the subtraction problem
![Count Back to Subract](/_next/image?url=https%3A%2F%2Fwww.turito.com%2Flearn-internal%2Fwp-content%2Fuploads%2F2023%2F07%2Fcount-back-to-subtract.png&w=1920&q=50)
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