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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. 12.6 + 18.4 = ____

    12.6 · 18.4 · Decimal addition

  2. 2. 13.2 + 8.8 = ____

    13.2 · 8.8 · Decimal addition

  3. 3. 11.0 + 4.1 = ____

    11.0 · 4.1 · Decimal addition

  4. 4. 15.1 + 11.1 = ____

    15.1 · 11.1 · Decimal addition

  5. 5. 14.1 + 11.7 = ____

    14.1 · 11.7 · Decimal addition

  6. 6. 18.1 + 11.9 = ____

    18.1 · 11.9 · Decimal addition

  7. 7. 3.9 + 10.5 = ____

    3.9 · 10.5 · Decimal addition

  8. 8. 5.2 + 18.7 = ____

    5.2 · 18.7 · Decimal addition

  9. 9. 4.4 + 6.8 = ____

    4.4 · 6.8 · Decimal addition

  10. 10. 5.2 + 12.0 = ____

    5.2 · 12.0 · Decimal addition

  11. 11. 5.5 + 7.3 = ____

    5.5 · 7.3 · Decimal addition

  12. 12. 8.9 + 18.0 = ____

    8.9 · 18.0 · Decimal addition
12 questions · Seed 104730 · 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. 12.6 + 18.4 = ____

    31.0

    Add 126 tenths and 184 tenths to get 310 tenths.

  2. 2. 13.2 + 8.8 = ____

    22.0

    Add 132 tenths and 88 tenths to get 220 tenths.

  3. 3. 11.0 + 4.1 = ____

    15.1

    Add 110 tenths and 41 tenths to get 151 tenths.

  4. 4. 15.1 + 11.1 = ____

    26.2

    Add 151 tenths and 111 tenths to get 262 tenths.

  5. 5. 14.1 + 11.7 = ____

    25.8

    Add 141 tenths and 117 tenths to get 258 tenths.

  6. 6. 18.1 + 11.9 = ____

    30.0

    Add 181 tenths and 119 tenths to get 300 tenths.

  7. 7. 3.9 + 10.5 = ____

    14.4

    Add 39 tenths and 105 tenths to get 144 tenths.

  8. 8. 5.2 + 18.7 = ____

    23.9

    Add 52 tenths and 187 tenths to get 239 tenths.

  9. 9. 4.4 + 6.8 = ____

    11.2

    Add 44 tenths and 68 tenths to get 112 tenths.

  10. 10. 5.2 + 12.0 = ____

    17.2

    Add 52 tenths and 120 tenths to get 172 tenths.

  11. 11. 5.5 + 7.3 = ____

    12.8

    Add 55 tenths and 73 tenths to get 128 tenths.

  12. 12. 8.9 + 18.0 = ____

    26.9

    Add 89 tenths and 180 tenths to get 269 tenths.

12 questions · Seed 104730 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 10-12

Decimal addition

Take your time. Show your thinking.

  1. 1. 12.6 + 18.4 = ____

    12.6 · 18.4 · Decimal addition

  2. 2. 13.2 + 8.8 = ____

    13.2 · 8.8 · Decimal addition

  3. 3. 11.0 + 4.1 = ____

    11.0 · 4.1 · Decimal addition

  4. 4. 15.1 + 11.1 = ____

    15.1 · 11.1 · Decimal addition

  5. 5. 14.1 + 11.7 = ____

    14.1 · 11.7 · Decimal addition

  6. 6. 18.1 + 11.9 = ____

    18.1 · 11.9 · Decimal addition

  7. 7. 3.9 + 10.5 = ____

    3.9 · 10.5 · Decimal addition

  8. 8. 5.2 + 18.7 = ____

    5.2 · 18.7 · Decimal addition

  9. 9. 4.4 + 6.8 = ____

    4.4 · 6.8 · Decimal addition

  10. 10. 5.2 + 12.0 = ____

    5.2 · 12.0 · Decimal addition

  11. 11. 5.5 + 7.3 = ____

    5.5 · 7.3 · Decimal addition

  12. 12. 8.9 + 18.0 = ____

    8.9 · 18.0 · Decimal addition
12 questions · Seed 104730 · Age guidance, not curriculum certification
Worksheet StudioAnswer key · Ages 10-12

Decimal addition

Answers and reasoning. Review before teaching.

  1. 1. 12.6 + 18.4 = ____

    31.0

    Add 126 tenths and 184 tenths to get 310 tenths.

  2. 2. 13.2 + 8.8 = ____

    22.0

    Add 132 tenths and 88 tenths to get 220 tenths.

  3. 3. 11.0 + 4.1 = ____

    15.1

    Add 110 tenths and 41 tenths to get 151 tenths.

  4. 4. 15.1 + 11.1 = ____

    26.2

    Add 151 tenths and 111 tenths to get 262 tenths.

  5. 5. 14.1 + 11.7 = ____

    25.8

    Add 141 tenths and 117 tenths to get 258 tenths.

  6. 6. 18.1 + 11.9 = ____

    30.0

    Add 181 tenths and 119 tenths to get 300 tenths.

  7. 7. 3.9 + 10.5 = ____

    14.4

    Add 39 tenths and 105 tenths to get 144 tenths.

  8. 8. 5.2 + 18.7 = ____

    23.9

    Add 52 tenths and 187 tenths to get 239 tenths.

  9. 9. 4.4 + 6.8 = ____

    11.2

    Add 44 tenths and 68 tenths to get 112 tenths.

  10. 10. 5.2 + 12.0 = ____

    17.2

    Add 52 tenths and 120 tenths to get 172 tenths.

  11. 11. 5.5 + 7.3 = ____

    12.8

    Add 55 tenths and 73 tenths to get 128 tenths.

  12. 12. 8.9 + 18.0 = ____

    26.9

    Add 89 tenths and 180 tenths to get 269 tenths.

12 questions · Seed 104730 · Age guidance, not curriculum certification