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Year 3 Maths — Adding 3-digit numbers

Add two numbers up to 999, carrying a ten or a hundred where you need to.

Name: ________________________

  1. 1.234 + 145 = ?

  2. 2.Put these sums in order, smallest answer first.

    • 101 + 102
    • 300 + 25
    • 150 + 60
    • 400 + 90

  3. 3.156 + 127 = ?

  4. 4.Tap where 320 + 40 lands.

    Mark the line with an X.

    300320340360380400

  5. 5.Sort each sum by whether a column has to be carried.

    Groups: No carrying · Carrying needed

    • 156 + 127
    • 245 + 137
    • 234 + 145
    • 321 + 456

  6. 6.348 + 256 = ?

    • a) 604
    • b) 594
    • c) 614
    • d) 704

  7. 7.Which sum gives 500?

    • a) 280 + 240
    • b) 260 + 240
    • c) 250 + 240
    • d) 270 + 240

  8. 8.406 + 90 = ?

Answer key — Year 3 Maths — Adding 3-digit numbers

  1. 1. 379
  2. 2. 1. 101 + 102 2. 150 + 60 3. 300 + 25 4. 400 + 90
  3. 3. 283
  4. 4. 360
  5. 5. 234 + 145 → No carrying; 156 + 127 → Carrying needed; 321 + 456 → No carrying; 245 + 137 → Carrying needed
  6. 6. a) 604
  7. 7. b) 260 + 240
  8. 8. 496