Adding Decimals

Name:

Date:

Calculator and decimal numbers illustration

🎯 WALT: Add decimal numbers accurately with correct decimal point placement

Success Criteria:

✓ I can align decimal points correctly when adding
✓ I can estimate sums to check my answers are reasonable
✓ I can solve decimal problems in real-life contexts

Instructions: Line up the decimal points carefully. Use estimation to check your answers make sense. Show your working by writing the equations in your book.

📊 Part 1: Number Equations (8 problems)

1. 3.4 + 2.6 = _______

2. 7.25 + 1.48 = _______

3. 12.7 + 8.35 = _______

4. 5.09 + 3.74 = _______

5. 15.6 + 7.89 = _______

6. 9.45 + 12.8 = _______

7. 6.375 + 4.29 = _______

8. 18.04 + 5.967 = _______

🏪 Part 2: Real-Life Word Problems (4 problems)

9. Ava buys a book for $12.75 and a pen for $3.40. How much does she spend in total?

10. Madeline is making cupcakes. The recipe needs 2.5 kilograms of flour and 1.75 kilograms of sugar. What is the total weight of these ingredients?

11. Joel runs 3.8 kilometres on Monday and 5.65 kilometres on Tuesday. What is his total distance?

12. The temperature rises from 18.7°C to 24.35°C during the day. What is the total temperature increase?

🚀 Extension Challenge: Multi-Digit Decimals

For advanced learners - try these harder problems!

13. 127.456 + 89.3782 = _______

14. 245.67 + 158.9345 + 73.28 = _______

15. Aaron measures three samples of chemicals: 15.6789g, 23.45g, and 8.901g. What is the total mass?

💡 Reflection & Self-Check

How confident do you feel about adding decimals? Circle one:

Very confident - I can do this easily!

Quite confident - I understand most of it

Need more practice - Some parts are tricky

Need help - I find this challenging

What strategy helped you most today?

📝 Answer Key (Teacher Use)

Part 1: 1) 6.0 2) 8.73 3) 21.05 4) 8.83 5) 23.49 6) 22.25 7) 10.665 8) 24.007

Part 2: 9) $16.15 10) 4.25kg 11) 9.45km 12) 5.65°C

Extension: 13) 216.8342 14) 477.8845 15) 48.0299g

Scaffolding Tips:

• Use decimal grids for visual learners
• Colour-code decimal points in blue
• Encourage estimation before calculating
• Provide extra spacing for students with dyslexia