Let's solve each problem step by step. The goal is to
find the missing addend in each addition equation. We can do this by
subtracting the known number from the total.
---
1) 2000 + ____ = 2300
Subtract:
2300 - 2000 =
300
✔ Answer:
300
---
2) ____ + 3500 = 5800
Subtract:
5800 - 3500 =
2300
✔ Answer:
2300
---
3) ____ + 1200 = 2500
Subtract:
2500 - 1200 =
1300
✔ Answer:
1300
---
4) 7400 + ____ = 10000
Subtract:
10000 - 7400 =
2600
✔ Answer:
2600
---
5) ____ + 900 = 1000
Subtract:
1000 - 900 =
100
✔ Answer:
100
---
6) ____ + 1500 = 5700
Subtract:
5700 - 1500 =
4200
✔ Answer:
4200
---
7) 5200 + ____ = 8100
Subtract:
8100 - 5200 =
2900
✔ Answer:
2900
---
8) 1100 + ____ = 2500
Subtract:
2500 - 1100 =
1400
✔ Answer:
1400
---
9) ____ + 400 = 2900
Subtract:
2900 - 400 =
2500
✔ Answer:
2500
---
10) 700 + ____ = 800
Subtract:
800 - 700 =
100
✔ Answer:
100
---
11) 3000 + ____ = 3200
Subtract:
3200 - 3000 =
200
✔ Answer:
200
---
12) 2700 + ____ = 3000
Subtract:
3000 - 2700 =
300
✔ Answer:
300
---
13) ____ + 2300 = 7900
Subtract:
7900 - 2300 =
5600
✔ Answer:
5600
---
14) ____ + 100 = 6200
Subtract:
6200 - 100 =
6100
✔ Answer:
6100
---
15) 1900 + ____ = 2300
Subtract:
2300 - 1900 =
400
✔ Answer:
400
---
16) ____ + 2400 = 8200
Subtract:
8200 - 2400 =
5800
✔ Answer:
5800
---
✔ Final Answers:
1)
300
2)
2300
3)
1300
4)
2600
5)
100
6)
4200
7)
2900
8)
1400
9)
2500
10)
100
11)
200
12)
300
13)
5600
14)
6100
15)
400
16)
5800
---
🔍 Explanation:
To find a missing addend, use the formula:
>
Missing Addend = Sum - Known Addend
This works because addition is commutative and subtraction is the inverse operation of addition.
For example:
If A + B = C, then B = C - A.
All these problems involve whole hundreds (multiples of 100), so you can also think in terms of "how many hundreds" are needed.
Let me know if you'd like a printable version or visual explanation!
Parent Tip: Review the logic above to help your child master the concept of 4th grade math addition and subtraction worksheet.
