Cardinal Math

Grade 3 · 3.NBT.1 · sheet 22 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 315 to the nearest ten
  2. 2 Round 375 to the nearest hundred
  3. 3 Round 883 to the nearest ten
  4. 4 Round 650 to the nearest hundred
  5. 5 Round 15 to the nearest ten
  6. 6 Round 172 to the nearest hundred
  7. 7 Round 21 to the nearest ten
  8. 8 Round 150 to the nearest hundred
  9. 9 Round 450 to the nearest hundred
  10. 10 Round 134 to the nearest hundred
  11. 11 Round 549 to the nearest hundred
  12. 12 Round 255 to the nearest ten
  13. 13 Round 582 to the nearest hundred
  14. 14 Round 254 to the nearest ten
  15. 15 Round 275 to the nearest hundred
  16. 16 Round 638 to the nearest hundred
  17. 17 Round 776 to the nearest ten
  18. 18 Round 963 to the nearest ten
  19. 19 Round 419 to the nearest ten
  20. 20 Round 163 to the nearest ten
Cardinal Math · sheet 22 key: cardinalmath.com/worksheets/rounding/22/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: rounding at the wrong place (14 problems), cutting the number off instead of rounding (12 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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