Free Grade 3 Decimals Lessons
Free Grade 3 lessons for Decimals: 12 real questions with a full answer key and worked solutions. Decimals extend place value past the ones: tenths, hundredths, thousandths. Line up decimal points when adding or subtracting.
Free
Core
15 min
24
Learning objectives
Every objective is checkable, and each one maps to an activity and an assessment.
- UnderstandExplain decimals
Explain decimals accurately in a familiar context.
Assessed by: Exit ticket of four short items
- ApplyCalculate decimals
Calculate decimals accurately in a familiar context.
Assessed by: Exit ticket of four short items
- AnalyseCompare decimals
Compare decimals accurately in a familiar context.
Assessed by: Exit ticket of four short items
- EvaluateJustify decimals
Justify decimals accurately in a familiar context.
Assessed by: Exit ticket of four short items
Prerequisites
Close these gaps first — each has its own free lesson, worksheet and quiz.
How Decimals works
Decimals extend place value past the ones: tenths, hundredths, thousandths. Line up decimal points when adding or subtracting.
12 practice questions
Easy to hard, 24 marks in total. Try them first, then open the answers.
- 1.76.4 − 17.7 = ?[1]
- 2.67.4 + 3.1 = ?[1]
- 3.34 + 76.4 = ?[1]
- 4.73.3 + 33.3 = ?[1]
- 5.9.23 − 2.18 = ?[2]
- 6.6.73 + 1.73 = ?[2]
- 7.5.92 + 6.8 = ?[2]
- 8.0.86 + 1.66 = ?[2]
- 9.0.731 × 8 = ?[3]
- 10.0.506 × 8 = ?[3]
- 11.0.523 × 7 = ?[3]
- 12.0.274 × 5 = ?[3]
Show answers and working
1. 58.7
Line up the decimal points. Fill gaps with zeros so both have 1 decimal place. Subtract as whole numbers: 58.7.
2. 70.5
Line up the decimal points. Fill gaps with zeros so both have 1 decimal place. Add as whole numbers: 70.5.
3. 110.4
Line up the decimal points. Fill gaps with zeros so both have 1 decimal place. Add as whole numbers: 110.4.
4. 106.6
Line up the decimal points. Fill gaps with zeros so both have 1 decimal place. Add as whole numbers: 106.6.
5. 7.05
Line up the decimal points. Fill gaps with zeros so both have 2 decimal places. Subtract as whole numbers: 7.05.
6. 8.46
Line up the decimal points. Fill gaps with zeros so both have 2 decimal places. Add as whole numbers: 8.46.
7. 12.72
Line up the decimal points. Fill gaps with zeros so both have 2 decimal places. Add as whole numbers: 12.72.
8. 2.52
Line up the decimal points. Fill gaps with zeros so both have 2 decimal places. Add as whole numbers: 2.52.
9. 5.848
Ignore the decimal: 731 × 8 = 5848. Put back 3 decimal places: 5.848.
10. 4.048
Ignore the decimal: 506 × 8 = 4048. Put back 3 decimal places: 4.048.
11. 3.661
Ignore the decimal: 523 × 7 = 3661. Put back 3 decimal places: 3.661.
12. 1.37
Ignore the decimal: 274 × 5 = 1370. Put back 3 decimal places: 1.37.
Worked examples
50.8 − 33.3 = ?
- Line up the decimal points.
- Fill gaps with zeros so both have 1 decimal place.
- Subtract as whole numbers: 17.5.
- Answer: 17.5
9.02 + 3.53 = ?
- Line up the decimal points.
- Fill gaps with zeros so both have 2 decimal places.
- Add as whole numbers: 12.55.
- Answer: 12.55
0.865 × 4 = ?
- Ignore the decimal: 865 × 4 = 3460.
- Put back 3 decimal places: 3.46.
- Answer: 3.46
Interactive practice
Free, no account required — answer on screen or print it.
Common mistakes
What learners typically get wrong, and how to fix it.
Thinks 0.25 is bigger than 0.3 because 25 > 3.
Correction: Fill with zeros: 0.25 vs 0.30.
Lines up the last digits instead of the decimal points.
Correction: Decimal points go in one straight column.
Teacher tips
- · Use money to make tenths and hundredths concrete.
Parent tips
- · Add up prices with cents together.
Real-life applications
- · Money, measurements, race times.
Assessment objectives
How mastery is evidenced, and which standards it maps to.
Every free resource for Decimals
One concept, one ecosystem — all of it free.
Goes deeper
The entities below this one, each with the same complete free resource set.
Sibling concepts
Related concepts
Lateral links, including across subjects.
Next topics
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Learn — Meet the idea.
Practice — Build fluency.
Revise — Keep it in memory.
Assess — Prove mastery.
Apply — Use it in context.
Teach — Deliver it to a class.
Frequently asked
- Is this Grade 3 Decimals lesson really free?
- Yes. Every lessons on FreeMathWorksheet is free to use, print and share — no account, no paywall and no watermark.
- What should a learner already know before this?
- Start with Fractions, Integers. Each one has its own free lesson, worksheet and quiz.
- How is the lesson sequenced?
- Recognition first, then understanding, application, reasoning and finally mastery — the same ladder used across every free resource on the platform.
- What comes next after Decimals?
- Move on to Percentages, Rational Numbers, Irrational Numbers, Real Numbers, which build directly on this idea.
Related resources
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