Worksheet skill
Decimal addition worksheets
Practice adding decimals. Choose the number range and how many decimal places to use before printing.
Sample worksheet
Download the sample worksheet and answer key, or open the builder to change the settings.
Download sample PDF
Change the settings
Before starting: Read tenths and hundredths and align numbers by place value, including placeholder zeros.
After this: Compare your sum with a whole-number estimate, then practice decimal subtraction.
Example questions
- 3.45 + 1.20 = ___
- 0.8 + 0.37 = ___
- 12.06 + 4.9 = ___
Settings in the builder
- decimal places
- number range
- vertical layout
Worked example
0.8 + 0.37
Answer: 1.17
How to solve it
Write 0.8 as 0.80. Add hundredths and tenths in aligned columns: 80 hundredths + 37 hundredths = 117 hundredths.
Common mistakes
What to check
- aligning digits instead of decimal points
- dropping placeholder zeros too early
Ways to review the work
- 1
Read each addend aloud by place value before calculating.
- 2
Ask whether the result should be smaller or larger than one before doing the example.
Teaching content updated 2026-09-05. Read our accuracy standards.