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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. 19.5 + 6.6 = ____

    19.5 · 6.6 · Decimal addition

  2. 2. 6.7 + 5.1 = ____

    6.7 · 5.1 · Decimal addition

  3. 3. 11.0 + 1.9 = ____

    11.0 · 1.9 · Decimal addition

  4. 4. 9.9 + 7.3 = ____

    9.9 · 7.3 · Decimal addition

  5. 5. 6.4 + 16.4 = ____

    6.4 · 16.4 · Decimal addition

  6. 6. 3.3 + 5.5 = ____

    3.3 · 5.5 · Decimal addition

  7. 7. 12.4 + 19.5 = ____

    12.4 · 19.5 · Decimal addition

  8. 8. 8.0 + 11.7 = ____

    8.0 · 11.7 · Decimal addition

  9. 9. 1.6 + 16.2 = ____

    1.6 · 16.2 · Decimal addition

  10. 10. 15.3 + 15.3 = ____

    15.3 · 15.3 · Decimal addition

  11. 11. 9.4 + 4.1 = ____

    9.4 · 4.1 · Decimal addition

  12. 12. 4.3 + 17.8 = ____

    4.3 · 17.8 · Decimal addition
12 questions · Seed 42 · 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. 19.5 + 6.6 = ____

    26.1

    Add 195 tenths and 66 tenths to get 261 tenths.

  2. 2. 6.7 + 5.1 = ____

    11.8

    Add 67 tenths and 51 tenths to get 118 tenths.

  3. 3. 11.0 + 1.9 = ____

    12.9

    Add 110 tenths and 19 tenths to get 129 tenths.

  4. 4. 9.9 + 7.3 = ____

    17.2

    Add 99 tenths and 73 tenths to get 172 tenths.

  5. 5. 6.4 + 16.4 = ____

    22.8

    Add 64 tenths and 164 tenths to get 228 tenths.

  6. 6. 3.3 + 5.5 = ____

    8.8

    Add 33 tenths and 55 tenths to get 88 tenths.

  7. 7. 12.4 + 19.5 = ____

    31.9

    Add 124 tenths and 195 tenths to get 319 tenths.

  8. 8. 8.0 + 11.7 = ____

    19.7

    Add 80 tenths and 117 tenths to get 197 tenths.

  9. 9. 1.6 + 16.2 = ____

    17.8

    Add 16 tenths and 162 tenths to get 178 tenths.

  10. 10. 15.3 + 15.3 = ____

    30.6

    Add 153 tenths and 153 tenths to get 306 tenths.

  11. 11. 9.4 + 4.1 = ____

    13.5

    Add 94 tenths and 41 tenths to get 135 tenths.

  12. 12. 4.3 + 17.8 = ____

    22.1

    Add 43 tenths and 178 tenths to get 221 tenths.

12 questions · Seed 42 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 10-12

Decimal addition

Take your time. Show your thinking.

  1. 1. 19.5 + 6.6 = ____

    19.5 · 6.6 · Decimal addition

  2. 2. 6.7 + 5.1 = ____

    6.7 · 5.1 · Decimal addition

  3. 3. 11.0 + 1.9 = ____

    11.0 · 1.9 · Decimal addition

  4. 4. 9.9 + 7.3 = ____

    9.9 · 7.3 · Decimal addition

  5. 5. 6.4 + 16.4 = ____

    6.4 · 16.4 · Decimal addition

  6. 6. 3.3 + 5.5 = ____

    3.3 · 5.5 · Decimal addition

  7. 7. 12.4 + 19.5 = ____

    12.4 · 19.5 · Decimal addition

  8. 8. 8.0 + 11.7 = ____

    8.0 · 11.7 · Decimal addition

  9. 9. 1.6 + 16.2 = ____

    1.6 · 16.2 · Decimal addition

  10. 10. 15.3 + 15.3 = ____

    15.3 · 15.3 · Decimal addition

  11. 11. 9.4 + 4.1 = ____

    9.4 · 4.1 · Decimal addition

  12. 12. 4.3 + 17.8 = ____

    4.3 · 17.8 · Decimal addition
12 questions · Seed 42 · Age guidance, not curriculum certification
Worksheet StudioAnswer key · Ages 10-12

Decimal addition

Answers and reasoning. Review before teaching.

  1. 1. 19.5 + 6.6 = ____

    26.1

    Add 195 tenths and 66 tenths to get 261 tenths.

  2. 2. 6.7 + 5.1 = ____

    11.8

    Add 67 tenths and 51 tenths to get 118 tenths.

  3. 3. 11.0 + 1.9 = ____

    12.9

    Add 110 tenths and 19 tenths to get 129 tenths.

  4. 4. 9.9 + 7.3 = ____

    17.2

    Add 99 tenths and 73 tenths to get 172 tenths.

  5. 5. 6.4 + 16.4 = ____

    22.8

    Add 64 tenths and 164 tenths to get 228 tenths.

  6. 6. 3.3 + 5.5 = ____

    8.8

    Add 33 tenths and 55 tenths to get 88 tenths.

  7. 7. 12.4 + 19.5 = ____

    31.9

    Add 124 tenths and 195 tenths to get 319 tenths.

  8. 8. 8.0 + 11.7 = ____

    19.7

    Add 80 tenths and 117 tenths to get 197 tenths.

  9. 9. 1.6 + 16.2 = ____

    17.8

    Add 16 tenths and 162 tenths to get 178 tenths.

  10. 10. 15.3 + 15.3 = ____

    30.6

    Add 153 tenths and 153 tenths to get 306 tenths.

  11. 11. 9.4 + 4.1 = ____

    13.5

    Add 94 tenths and 41 tenths to get 135 tenths.

  12. 12. 4.3 + 17.8 = ____

    22.1

    Add 43 tenths and 178 tenths to get 221 tenths.

12 questions · Seed 42 · Age guidance, not curriculum certification