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Missing Numbers - Worksheet 9 - 1st Grade

Hard

Find missing numbers in subtraction equations (Hard)

23 problems · 10-15 minutes · Skills: subtraction, algebraic thinking

About This Worksheet

This hard-level worksheet contains 23 problems designed for 1st Grade students practicing missing numbers. Hard worksheets feature challenging problems including multi-step questions, missing values, and real-world applications to push students further.

Finding missing values in subtraction builds algebraic reasoning and reinforces the connection between addition and subtraction.

How to Solve: Worked Example

Example Problem: 15 − ___ = 8
Solution Steps:
  1. Subtract: 15 − 8 = 7.
  2. The missing number is 7.
  3. Check: 15 − 7 = 8. Correct!
Answer: 7
Tip: Always verify your answer by plugging it back into the equation.
1
12 - 7 = ___
2
20 - ___ = 14
3
___ - 14 = 2
4
___ - 9 = 2
5
___ - 4 = 6
6
13 - ___ = 8
7
___ - 7 = 6
8
13 - ___ = 2
9
18 - 12 = ___
10
18 - 5 = ___
11
17 - ___ = 5
12
10 - ___ = 7
13
15 - ___ = 9
14
___ - 6 = 10
15
___ - 3 = 9
16
16 - ___ = 8
17
___ - 8 = 2
18
___ - 4 = 13
19
15 - ___ = 2
20
17 - ___ = 5
21
___ - 9 = 11
22
13 - ___ = 7
23
20 - ___ = 3

Answer Key

1. 52. 63. 164. 115. 106. 57. 138. 119. 610. 1311. 1212. 313. 614. 1615. 1216. 817. 1018. 1719. 1320. 1221. 2022. 623. 17

Frequently Asked Questions

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How many problems are on this worksheet?

This worksheet contains 23 problems. It typically takes 10-15 minutes to complete. An answer key with all solutions is included.