← Squares next to a ten lesson New set →

Squares Trick Worksheet

Speed calculation lesson 10: Squares next to a ten · Set 688 · 40 questions
TalentJR

The fast method (Step from a neighbour): Find the round neighbour and square it: 70² = 7 × 7 = 49, then two 0s → 4900. Ends in 1 (one more)? Add the round number and the number: 4900 + 70 + 71. Ends in 9 (one less)? Take them away: 69² = 4900 − 70 − 69 = 4761.

NameDateTime takenScore ___ / 40
  1. 1.91² =
  2. 2.81² =
  3. 3.59² =
  4. 4.31² =
  5. 5.49² =
  6. 6.51² =
  7. 7.49² =
  8. 8.79² =
  9. 9.79² =
  10. 10.49² =
  11. 11.29² =
  12. 12.39² =
  13. 13.81² =
  14. 14.39² =
  15. 15.31² =
  16. 16.81² =
  17. 17.91² =
  18. 18.49² =
  19. 19.21² =
  20. 20.89² =
  21. 21.31² =
  22. 22.51² =
  23. 23.41² =
  24. 24.51² =
  25. 25.29² =
  26. 26.19² =
  27. 27.59² =
  28. 28.51² =
  29. 29.59² =
  30. 30.21² =
  31. 31.21² =
  32. 32.61² =
  33. 33.69² =
  34. 34.71² =
  35. 35.19² =
  36. 36.59² =
  37. 37.59² =
  38. 38.21² =
  39. 39.41² =
  40. 40.91² =

Answer key

  1. 8281
  2. 6561
  3. 3481
  4. 961
  5. 2401
  6. 2601
  7. 2401
  8. 6241
  9. 6241
  10. 2401
  11. 841
  12. 1521
  13. 6561
  14. 1521
  15. 961
  16. 6561
  17. 8281
  18. 2401
  19. 441
  20. 7921
  21. 961
  22. 2601
  23. 1681
  24. 2601
  25. 841
  26. 361
  27. 3481
  28. 2601
  29. 3481
  30. 441
  31. 441
  32. 3721
  33. 4761
  34. 5041
  35. 361
  36. 3481
  37. 3481
  38. 441
  39. 1681
  40. 8281

Free speed calculation lessons, practice and worksheets at talentjr.in/speed-maths