To solve these problems, we need to find the missing number (the addend) that makes each equation true. We can do this by using subtraction — because addition and subtraction are opposites.
For example:
If you have 9 + ___ = 15,
you can think: “What number added to 9 gives 15?”
Or: “15 minus 9 equals what?” → 15 - 9 = 6.
So the missing number is 6.
Let’s go one by one:
---
Left Column:
1. 9 + ___ = 15 → 15 - 9 =
6
2. ___ + 5 = 13 → 13 - 5 =
8
3. 8 + ___ = 16 → 16 - 8 =
8
4. ___ + 7 = 14 → 14 - 7 =
7
5. 3 + ___ = 10 → 10 - 3 =
7
6. ___ + 2 = 11 → 11 - 2 =
9
7. 9 + ___ = 18 → 18 - 9 =
9
8. ___ + 6 = 13 → 13 - 6 =
7
9. 5 + ___ = 12 → 12 - 5 =
7
---
Right Column:
1. ___ + 8 = 14 → 14 - 8 =
6
2. 5 + ___ = 13 → 13 - 5 =
8
3. ___ + 3 = 12 → 12 - 3 =
9
4. 7 + ___ = 15 → 15 - 7 =
8
5. ___ + 6 = 14 → 14 - 6 =
8
6. 5 + ___ = 16 → 16 - 5 =
11
7. ___ + 2 = 10 → 10 - 2 =
8
8. 6 + ___ = 13 → 13 - 6 =
7
9. ___ + 8 = 17 → 17 - 8 =
9
---
Double-checking a few to make sure:
- 9 + 6 = 15
✔
- 8 + 5 = 13
✔
- 8 + 8 = 16
✔
- 7 + 7 = 14
✔
- 3 + 7 = 10
✔
- 9 + 2 = 11
✔
- 9 + 9 = 18
✔
- 7 + 6 = 13
✔
- 5 + 7 = 12
✔
Right side:
- 6 + 8 = 14
✔
- 5 + 8 = 13
✔
- 9 + 3 = 12
✔
- 7 + 8 = 15
✔
- 8 + 6 = 14
✔
- 5 + 11 = 16
✔
- 8 + 2 = 10
✔
- 6 + 7 = 13
✔
- 9 + 8 = 17
✔
All correct!
Final Answer:
Left column answers (top to bottom): 6, 8, 8, 7, 7, 9, 9, 7, 7
Right column answers (top to bottom): 6, 8, 9, 8, 8, 11, 8, 7, 9
Parent Tip: Review the logic above to help your child master the concept of 2nd grade math worksheet printable free.
