← Squares next to a ten lesson New set →

Squares Trick Worksheet

Speed calculation lesson 10: Squares next to a ten · Set 724 · 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. 1.69² =
  2. 2.49² =
  3. 3.19² =
  4. 4.69² =
  5. 5.19² =
  6. 6.39² =
  7. 7.71² =
  8. 8.89² =
  9. 9.79² =
  10. 10.61² =
  11. 11.79² =
  12. 12.69² =
  13. 13.61² =
  14. 14.71² =
  15. 15.39² =
  16. 16.29² =
  17. 17.61² =
  18. 18.31² =
  19. 19.19² =
  20. 20.31² =
  21. 21.29² =
  22. 22.31² =
  23. 23.69² =
  24. 24.69² =
  25. 25.91² =
  26. 26.91² =
  27. 27.39² =
  28. 28.39² =
  29. 29.21² =
  30. 30.61² =
  31. 31.69² =
  32. 32.41² =
  33. 33.29² =
  34. 34.89² =
  35. 35.91² =
  36. 36.59² =
  37. 37.41² =
  38. 38.19² =
  39. 39.59² =
  40. 40.89² =

Answer key

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

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