← Squares next to a ten lesson New set →

Squares Trick Worksheet

Speed calculation lesson 10: Squares next to a ten · Set 391 · 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. 1.29² =
  2. 2.19² =
  3. 3.89² =
  4. 4.29² =
  5. 5.81² =
  6. 6.19² =
  7. 7.51² =
  8. 8.31² =
  9. 9.91² =
  10. 10.39² =
  11. 11.59² =
  12. 12.39² =
  13. 13.79² =
  14. 14.79² =
  15. 15.89² =
  16. 16.51² =
  17. 17.21² =
  18. 18.69² =
  19. 19.69² =
  20. 20.21² =
  21. 21.89² =
  22. 22.81² =
  23. 23.81² =
  24. 24.19² =
  25. 25.19² =
  26. 26.91² =
  27. 27.91² =
  28. 28.89² =
  29. 29.41² =
  30. 30.61² =
  31. 31.59² =
  32. 32.71² =
  33. 33.89² =
  34. 34.69² =
  35. 35.61² =
  36. 36.69² =
  37. 37.69² =
  38. 38.29² =
  39. 39.61² =
  40. 40.39² =

Answer key

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

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