← Back to Subtraction within 20

Subtraction within 20 - Worksheet 1 - 1st Grade

Easy

Subtract with minuends up to 20 (Easy)

20 problems · 10-15 minutes · Skills: subtraction, mental math

About This Worksheet

This easy-level worksheet contains 20 problems designed for 1st Grade students practicing subtraction within 20. Easy worksheets use simpler numbers and straightforward problem types to build confidence and reinforce foundational skills.

Subtraction across ten is a key milestone. The strategies learned here — like breaking apart numbers — apply to subtracting much larger numbers.

How to Solve: Worked Example

Example Problem: 10 − 3 = ___
Solution Steps:
  1. Start at 10.
  2. Count back 3: 9, 8, 7.
  3. 10 − 3 = 7.
Answer: 7
Tip: Subtracting from 10 is a key skill — memorize your "subtract from 10" facts!
1
12 - 3 =
2
10 - 2 =
3
12 - 3 =
4
5 - 1 =
5
12 - 1 =
6
8 - 3 =
7
11 - 3 =
8
12 - 3 =
9
9 - 2 =
10
11 - 4 =
11
12 - 5 =
12
12 - 1 =
13
8 - 4 =
14
12 - 2 =
15
12 - 3 =
16
10 - 2 =
17
9 - 4 =
18
12 - 2 =
19
8 - 2 =
20
12 - 1 =

Answer Key

1. 92. 83. 94. 45. 116. 57. 88. 99. 710. 711. 712. 1113. 414. 1015. 916. 817. 518. 1019. 620. 11

Frequently Asked Questions

How do I download this subtraction within 20 - worksheet 1 worksheet?

Click the "Download PDF / Print" button at the top of the worksheet. You can save it as a PDF or print it directly. The answer key will be on a separate page.

How do I find worksheets at different difficulty levels?

Each subtopic has 10 worksheets: Worksheets 1-3 are Easy, 4-7 are Medium, and 8-10 are Hard. Start with Easy worksheets to build confidence, then progress to harder ones.

How many problems are on this worksheet?

This worksheet contains 20 problems. It typically takes 10-15 minutes to complete. An answer key with all solutions is included.