Cardinal Math

Grade 3 · 3.NBT.1 · sheet 3 of 30

Rounding to the nearest ten and hundred

A printable worksheet, new every day, with a key that names the mistake.

  • Ten numbers to round to the nearest ten and ten to the nearest hundred, three of each sitting exactly halfway.
  • The key names the two usual mistakes: cutting the number off instead of rounding, and looking at the wrong digit.
Answer key Another sheet →

Rounding to the nearest ten and hundred

Round each number. Halfway rounds up.

Name Date
  1. 1 Round 732 to the nearest ten
  2. 2 Round 850 to the nearest hundred
  3. 3 Round 324 to the nearest hundred
  4. 4 Round 870 to the nearest hundred
  5. 5 Round 144 to the nearest ten
  6. 6 Round 479 to the nearest ten
  7. 7 Round 579 to the nearest hundred
  8. 8 Round 278 to the nearest ten
  9. 9 Round 328 to the nearest ten
  10. 10 Round 772 to the nearest hundred
  11. 11 Round 178 to the nearest ten
  12. 12 Round 715 to the nearest ten
  13. 13 Round 395 to the nearest ten
  14. 14 Round 350 to the nearest hundred
  15. 15 Round 456 to the nearest hundred
  16. 16 Round 577 to the nearest hundred
  17. 17 Round 650 to the nearest hundred
  18. 18 Round 195 to the nearest hundred
  19. 19 Round 528 to the nearest ten
  20. 20 Round 125 to the nearest ten
Cardinal Math · sheet 3 key: cardinalmath.com/worksheets/rounding/3/key/

The app does this live.

It picks the next problem from the last answer, skips ahead or doubles back, and animates the teaching instead of handing over a rule. Inside the app the same patterns the key names are caught as your child plays.

How to use the key

Mark the sheet against the key. Beside each answer it lists what the known mistakes would have written. One wrong answer is a slip. The same pattern three times is a rule your child is following, and the guide says what to do about it tonight.

On this sheet the key can tell apart: cutting the number off instead of rounding (17 problems), rounding at the wrong place (7 problems).

Cardinal Math watches for all of these, every day.

Inside the app the same patterns are caught as your child plays, across the whole of K to grade 5, and explained to you in plain words. One price, no ads, no streaks. Coming to iPhone and iPad.

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