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Missing Addends - Worksheet 5 - 1st Grade

Medium

Find the missing number in addition equations (Medium)

18 problems · 10-15 minutes · Skills: addition, algebraic thinking

About This Worksheet

This medium-level worksheet contains 18 problems designed for 1st Grade students practicing missing addends. Medium worksheets introduce larger numbers and varied question formats to deepen understanding and build fluency.

Missing addend problems introduce algebraic thinking — finding an unknown value. This prepares students for equation solving in later grades.

How to Solve: Worked Example

Example Problem: 6 + ___ = 12
Solution Steps:
  1. Think: 6 + ? = 12.
  2. Use subtraction: 12 − 6 = 6.
  3. The missing number is 6.
Answer: 6
Tip: Subtraction is the opposite of addition — use it to find missing parts!
1
9 + ___ = 14
2
4 + ___ = 13
3
2 + ___ = 8
4
8 + ___ = 11
5
3 + ___ = 14
6
2 + ___ = 11
7
3 + ___ = 14
8
3 + ___ = 8
9
3 + ___ = 14
10
5 + ___ = 10
11
7 + ___ = 9
12
5 + ___ = 9
13
6 + ___ = 11
14
5 + ___ = 9
15
3 + ___ = 9
16
3 + ___ = 13
17
5 + ___ = 10
18
2 + ___ = 12

Answer Key

1. 52. 93. 64. 35. 116. 97. 118. 59. 1110. 511. 212. 413. 514. 415. 616. 1017. 518. 10

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How many problems are on this worksheet?

This worksheet contains 18 problems. It typically takes 10-15 minutes to complete. An answer key with all solutions is included.