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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. 16.6 + 18.3 = ____

    16.6 · 18.3 · Decimal addition

  2. 2. 5.5 + 6.5 = ____

    5.5 · 6.5 · Decimal addition

  3. 3. 1.3 + 5.5 = ____

    1.3 · 5.5 · Decimal addition

  4. 4. 3.5 + 17.0 = ____

    3.5 · 17.0 · Decimal addition

  5. 5. 4.0 + 17.8 = ____

    4.0 · 17.8 · Decimal addition

  6. 6. 12.4 + 6.7 = ____

    12.4 · 6.7 · Decimal addition

  7. 7. 9.1 + 4.1 = ____

    9.1 · 4.1 · Decimal addition

  8. 8. 1.3 + 18.1 = ____

    1.3 · 18.1 · Decimal addition

  9. 9. 4.3 + 3.7 = ____

    4.3 · 3.7 · Decimal addition

  10. 10. 17.0 + 1.4 = ____

    17.0 · 1.4 · Decimal addition

  11. 11. 14.5 + 15.8 = ____

    14.5 · 15.8 · Decimal addition

  12. 12. 17.2 + 6.5 = ____

    17.2 · 6.5 · Decimal addition
12 questions · Seed 104733 · 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. 16.6 + 18.3 = ____

    34.9

    Add 166 tenths and 183 tenths to get 349 tenths.

  2. 2. 5.5 + 6.5 = ____

    12.0

    Add 55 tenths and 65 tenths to get 120 tenths.

  3. 3. 1.3 + 5.5 = ____

    6.8

    Add 13 tenths and 55 tenths to get 68 tenths.

  4. 4. 3.5 + 17.0 = ____

    20.5

    Add 35 tenths and 170 tenths to get 205 tenths.

  5. 5. 4.0 + 17.8 = ____

    21.8

    Add 40 tenths and 178 tenths to get 218 tenths.

  6. 6. 12.4 + 6.7 = ____

    19.1

    Add 124 tenths and 67 tenths to get 191 tenths.

  7. 7. 9.1 + 4.1 = ____

    13.2

    Add 91 tenths and 41 tenths to get 132 tenths.

  8. 8. 1.3 + 18.1 = ____

    19.4

    Add 13 tenths and 181 tenths to get 194 tenths.

  9. 9. 4.3 + 3.7 = ____

    8.0

    Add 43 tenths and 37 tenths to get 80 tenths.

  10. 10. 17.0 + 1.4 = ____

    18.4

    Add 170 tenths and 14 tenths to get 184 tenths.

  11. 11. 14.5 + 15.8 = ____

    30.3

    Add 145 tenths and 158 tenths to get 303 tenths.

  12. 12. 17.2 + 6.5 = ____

    23.7

    Add 172 tenths and 65 tenths to get 237 tenths.

12 questions · Seed 104733 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 10-12

Decimal addition

Take your time. Show your thinking.

  1. 1. 16.6 + 18.3 = ____

    16.6 · 18.3 · Decimal addition

  2. 2. 5.5 + 6.5 = ____

    5.5 · 6.5 · Decimal addition

  3. 3. 1.3 + 5.5 = ____

    1.3 · 5.5 · Decimal addition

  4. 4. 3.5 + 17.0 = ____

    3.5 · 17.0 · Decimal addition

  5. 5. 4.0 + 17.8 = ____

    4.0 · 17.8 · Decimal addition

  6. 6. 12.4 + 6.7 = ____

    12.4 · 6.7 · Decimal addition

  7. 7. 9.1 + 4.1 = ____

    9.1 · 4.1 · Decimal addition

  8. 8. 1.3 + 18.1 = ____

    1.3 · 18.1 · Decimal addition

  9. 9. 4.3 + 3.7 = ____

    4.3 · 3.7 · Decimal addition

  10. 10. 17.0 + 1.4 = ____

    17.0 · 1.4 · Decimal addition

  11. 11. 14.5 + 15.8 = ____

    14.5 · 15.8 · Decimal addition

  12. 12. 17.2 + 6.5 = ____

    17.2 · 6.5 · Decimal addition
12 questions · Seed 104733 · Age guidance, not curriculum certification
Worksheet StudioAnswer key · Ages 10-12

Decimal addition

Answers and reasoning. Review before teaching.

  1. 1. 16.6 + 18.3 = ____

    34.9

    Add 166 tenths and 183 tenths to get 349 tenths.

  2. 2. 5.5 + 6.5 = ____

    12.0

    Add 55 tenths and 65 tenths to get 120 tenths.

  3. 3. 1.3 + 5.5 = ____

    6.8

    Add 13 tenths and 55 tenths to get 68 tenths.

  4. 4. 3.5 + 17.0 = ____

    20.5

    Add 35 tenths and 170 tenths to get 205 tenths.

  5. 5. 4.0 + 17.8 = ____

    21.8

    Add 40 tenths and 178 tenths to get 218 tenths.

  6. 6. 12.4 + 6.7 = ____

    19.1

    Add 124 tenths and 67 tenths to get 191 tenths.

  7. 7. 9.1 + 4.1 = ____

    13.2

    Add 91 tenths and 41 tenths to get 132 tenths.

  8. 8. 1.3 + 18.1 = ____

    19.4

    Add 13 tenths and 181 tenths to get 194 tenths.

  9. 9. 4.3 + 3.7 = ____

    8.0

    Add 43 tenths and 37 tenths to get 80 tenths.

  10. 10. 17.0 + 1.4 = ____

    18.4

    Add 170 tenths and 14 tenths to get 184 tenths.

  11. 11. 14.5 + 15.8 = ____

    30.3

    Add 145 tenths and 158 tenths to get 303 tenths.

  12. 12. 17.2 + 6.5 = ____

    23.7

    Add 172 tenths and 65 tenths to get 237 tenths.

12 questions · Seed 104733 · Age guidance, not curriculum certification