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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. 17.2 + 13.3 = ____

    17.2 · 13.3 · Decimal addition

  2. 2. 12.2 + 12.9 = ____

    12.2 · 12.9 · Decimal addition

  3. 3. 16.9 + 18.8 = ____

    16.9 · 18.8 · Decimal addition

  4. 4. 8.2 + 4.3 = ____

    8.2 · 4.3 · Decimal addition

  5. 5. 1.8 + 18.0 = ____

    1.8 · 18.0 · Decimal addition

  6. 6. 5.7 + 15.4 = ____

    5.7 · 15.4 · Decimal addition

  7. 7. 16.8 + 11.4 = ____

    16.8 · 11.4 · Decimal addition

  8. 8. 4.1 + 3.9 = ____

    4.1 · 3.9 · Decimal addition

  9. 9. 14.0 + 7.5 = ____

    14.0 · 7.5 · Decimal addition

  10. 10. 7.3 + 13.6 = ____

    7.3 · 13.6 · Decimal addition

  11. 11. 3.0 + 12.5 = ____

    3.0 · 12.5 · Decimal addition

  12. 12. 10.9 + 17.8 = ____

    10.9 · 17.8 · Decimal addition
12 questions · Seed 104731 · 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. 17.2 + 13.3 = ____

    30.5

    Add 172 tenths and 133 tenths to get 305 tenths.

  2. 2. 12.2 + 12.9 = ____

    25.1

    Add 122 tenths and 129 tenths to get 251 tenths.

  3. 3. 16.9 + 18.8 = ____

    35.7

    Add 169 tenths and 188 tenths to get 357 tenths.

  4. 4. 8.2 + 4.3 = ____

    12.5

    Add 82 tenths and 43 tenths to get 125 tenths.

  5. 5. 1.8 + 18.0 = ____

    19.8

    Add 18 tenths and 180 tenths to get 198 tenths.

  6. 6. 5.7 + 15.4 = ____

    21.1

    Add 57 tenths and 154 tenths to get 211 tenths.

  7. 7. 16.8 + 11.4 = ____

    28.2

    Add 168 tenths and 114 tenths to get 282 tenths.

  8. 8. 4.1 + 3.9 = ____

    8.0

    Add 41 tenths and 39 tenths to get 80 tenths.

  9. 9. 14.0 + 7.5 = ____

    21.5

    Add 140 tenths and 75 tenths to get 215 tenths.

  10. 10. 7.3 + 13.6 = ____

    20.9

    Add 73 tenths and 136 tenths to get 209 tenths.

  11. 11. 3.0 + 12.5 = ____

    15.5

    Add 30 tenths and 125 tenths to get 155 tenths.

  12. 12. 10.9 + 17.8 = ____

    28.7

    Add 109 tenths and 178 tenths to get 287 tenths.

12 questions · Seed 104731 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 10-12

Decimal addition

Take your time. Show your thinking.

  1. 1. 17.2 + 13.3 = ____

    17.2 · 13.3 · Decimal addition

  2. 2. 12.2 + 12.9 = ____

    12.2 · 12.9 · Decimal addition

  3. 3. 16.9 + 18.8 = ____

    16.9 · 18.8 · Decimal addition

  4. 4. 8.2 + 4.3 = ____

    8.2 · 4.3 · Decimal addition

  5. 5. 1.8 + 18.0 = ____

    1.8 · 18.0 · Decimal addition

  6. 6. 5.7 + 15.4 = ____

    5.7 · 15.4 · Decimal addition

  7. 7. 16.8 + 11.4 = ____

    16.8 · 11.4 · Decimal addition

  8. 8. 4.1 + 3.9 = ____

    4.1 · 3.9 · Decimal addition

  9. 9. 14.0 + 7.5 = ____

    14.0 · 7.5 · Decimal addition

  10. 10. 7.3 + 13.6 = ____

    7.3 · 13.6 · Decimal addition

  11. 11. 3.0 + 12.5 = ____

    3.0 · 12.5 · Decimal addition

  12. 12. 10.9 + 17.8 = ____

    10.9 · 17.8 · Decimal addition
12 questions · Seed 104731 · Age guidance, not curriculum certification
Worksheet StudioAnswer key · Ages 10-12

Decimal addition

Answers and reasoning. Review before teaching.

  1. 1. 17.2 + 13.3 = ____

    30.5

    Add 172 tenths and 133 tenths to get 305 tenths.

  2. 2. 12.2 + 12.9 = ____

    25.1

    Add 122 tenths and 129 tenths to get 251 tenths.

  3. 3. 16.9 + 18.8 = ____

    35.7

    Add 169 tenths and 188 tenths to get 357 tenths.

  4. 4. 8.2 + 4.3 = ____

    12.5

    Add 82 tenths and 43 tenths to get 125 tenths.

  5. 5. 1.8 + 18.0 = ____

    19.8

    Add 18 tenths and 180 tenths to get 198 tenths.

  6. 6. 5.7 + 15.4 = ____

    21.1

    Add 57 tenths and 154 tenths to get 211 tenths.

  7. 7. 16.8 + 11.4 = ____

    28.2

    Add 168 tenths and 114 tenths to get 282 tenths.

  8. 8. 4.1 + 3.9 = ____

    8.0

    Add 41 tenths and 39 tenths to get 80 tenths.

  9. 9. 14.0 + 7.5 = ____

    21.5

    Add 140 tenths and 75 tenths to get 215 tenths.

  10. 10. 7.3 + 13.6 = ____

    20.9

    Add 73 tenths and 136 tenths to get 209 tenths.

  11. 11. 3.0 + 12.5 = ____

    15.5

    Add 30 tenths and 125 tenths to get 155 tenths.

  12. 12. 10.9 + 17.8 = ____

    28.7

    Add 109 tenths and 178 tenths to get 287 tenths.

12 questions · Seed 104731 · Age guidance, not curriculum certification