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MathsAges 10-12

Decimal addition

Add numbers in tenths. Keep the decimal places aligned as you calculate. Review suitability for your learners before teaching.

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Worksheet StudioPractice pack · Ages 10-12

Decimal addition

Take your time. Show your thinking.

  1. 1. 17.8 + 11.0 = ____

    17.8 · 11.0 · Decimal addition

  2. 2. 12.4 + 14.9 = ____

    12.4 · 14.9 · Decimal addition

  3. 3. 5.3 + 14.9 = ____

    5.3 · 14.9 · Decimal addition

  4. 4. 18.0 + 15.6 = ____

    18.0 · 15.6 · Decimal addition

  5. 5. 2.6 + 10.4 = ____

    2.6 · 10.4 · Decimal addition

  6. 6. 2.6 + 10.0 = ____

    2.6 · 10.0 · Decimal addition

  7. 7. 3.8 + 17.8 = ____

    3.8 · 17.8 · Decimal addition

  8. 8. 13.5 + 1.2 = ____

    13.5 · 1.2 · Decimal addition

  9. 9. 12.2 + 3.6 = ____

    12.2 · 3.6 · Decimal addition

  10. 10. 12.6 + 1.3 = ____

    12.6 · 1.3 · Decimal addition

  11. 11. 7.3 + 1.6 = ____

    7.3 · 1.6 · Decimal addition

  12. 12. 6.6 + 8.3 = ____

    6.6 · 8.3 · Decimal addition
12 questions · Seed 43 · Age guidance, not curriculum certification
View the answer key
Worksheet StudioAnswer key · Ages 10-12

Decimal addition

Answers and reasoning. Review before teaching.

  1. 1. 17.8 + 11.0 = ____

    28.8

    Add 178 tenths and 110 tenths to get 288 tenths.

  2. 2. 12.4 + 14.9 = ____

    27.3

    Add 124 tenths and 149 tenths to get 273 tenths.

  3. 3. 5.3 + 14.9 = ____

    20.2

    Add 53 tenths and 149 tenths to get 202 tenths.

  4. 4. 18.0 + 15.6 = ____

    33.6

    Add 180 tenths and 156 tenths to get 336 tenths.

  5. 5. 2.6 + 10.4 = ____

    13.0

    Add 26 tenths and 104 tenths to get 130 tenths.

  6. 6. 2.6 + 10.0 = ____

    12.6

    Add 26 tenths and 100 tenths to get 126 tenths.

  7. 7. 3.8 + 17.8 = ____

    21.6

    Add 38 tenths and 178 tenths to get 216 tenths.

  8. 8. 13.5 + 1.2 = ____

    14.7

    Add 135 tenths and 12 tenths to get 147 tenths.

  9. 9. 12.2 + 3.6 = ____

    15.8

    Add 122 tenths and 36 tenths to get 158 tenths.

  10. 10. 12.6 + 1.3 = ____

    13.9

    Add 126 tenths and 13 tenths to get 139 tenths.

  11. 11. 7.3 + 1.6 = ____

    8.9

    Add 73 tenths and 16 tenths to get 89 tenths.

  12. 12. 6.6 + 8.3 = ____

    14.9

    Add 66 tenths and 83 tenths to get 149 tenths.

12 questions · Seed 43 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 10-12

Decimal addition

Take your time. Show your thinking.

  1. 1. 17.8 + 11.0 = ____

    17.8 · 11.0 · Decimal addition

  2. 2. 12.4 + 14.9 = ____

    12.4 · 14.9 · Decimal addition

  3. 3. 5.3 + 14.9 = ____

    5.3 · 14.9 · Decimal addition

  4. 4. 18.0 + 15.6 = ____

    18.0 · 15.6 · Decimal addition

  5. 5. 2.6 + 10.4 = ____

    2.6 · 10.4 · Decimal addition

  6. 6. 2.6 + 10.0 = ____

    2.6 · 10.0 · Decimal addition

  7. 7. 3.8 + 17.8 = ____

    3.8 · 17.8 · Decimal addition

  8. 8. 13.5 + 1.2 = ____

    13.5 · 1.2 · Decimal addition

  9. 9. 12.2 + 3.6 = ____

    12.2 · 3.6 · Decimal addition

  10. 10. 12.6 + 1.3 = ____

    12.6 · 1.3 · Decimal addition

  11. 11. 7.3 + 1.6 = ____

    7.3 · 1.6 · Decimal addition

  12. 12. 6.6 + 8.3 = ____

    6.6 · 8.3 · Decimal addition
12 questions · Seed 43 · Age guidance, not curriculum certification
Worksheet StudioAnswer key · Ages 10-12

Decimal addition

Answers and reasoning. Review before teaching.

  1. 1. 17.8 + 11.0 = ____

    28.8

    Add 178 tenths and 110 tenths to get 288 tenths.

  2. 2. 12.4 + 14.9 = ____

    27.3

    Add 124 tenths and 149 tenths to get 273 tenths.

  3. 3. 5.3 + 14.9 = ____

    20.2

    Add 53 tenths and 149 tenths to get 202 tenths.

  4. 4. 18.0 + 15.6 = ____

    33.6

    Add 180 tenths and 156 tenths to get 336 tenths.

  5. 5. 2.6 + 10.4 = ____

    13.0

    Add 26 tenths and 104 tenths to get 130 tenths.

  6. 6. 2.6 + 10.0 = ____

    12.6

    Add 26 tenths and 100 tenths to get 126 tenths.

  7. 7. 3.8 + 17.8 = ____

    21.6

    Add 38 tenths and 178 tenths to get 216 tenths.

  8. 8. 13.5 + 1.2 = ____

    14.7

    Add 135 tenths and 12 tenths to get 147 tenths.

  9. 9. 12.2 + 3.6 = ____

    15.8

    Add 122 tenths and 36 tenths to get 158 tenths.

  10. 10. 12.6 + 1.3 = ____

    13.9

    Add 126 tenths and 13 tenths to get 139 tenths.

  11. 11. 7.3 + 1.6 = ____

    8.9

    Add 73 tenths and 16 tenths to get 89 tenths.

  12. 12. 6.6 + 8.3 = ____

    14.9

    Add 66 tenths and 83 tenths to get 149 tenths.

12 questions · Seed 43 · Age guidance, not curriculum certification