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Squares Trick Worksheet

Speed calculation lesson 10: Squares next to a ten · Set 998 · 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. 1.21² =
  2. 2.91² =
  3. 3.71² =
  4. 4.81² =
  5. 5.49² =
  6. 6.29² =
  7. 7.71² =
  8. 8.91² =
  9. 9.19² =
  10. 10.79² =
  11. 11.29² =
  12. 12.81² =
  13. 13.71² =
  14. 14.69² =
  15. 15.81² =
  16. 16.39² =
  17. 17.21² =
  18. 18.79² =
  19. 19.61² =
  20. 20.69² =
  21. 21.69² =
  22. 22.89² =
  23. 23.19² =
  24. 24.29² =
  25. 25.41² =
  26. 26.49² =
  27. 27.49² =
  28. 28.89² =
  29. 29.21² =
  30. 30.71² =
  31. 31.81² =
  32. 32.69² =
  33. 33.69² =
  34. 34.49² =
  35. 35.39² =
  36. 36.89² =
  37. 37.79² =
  38. 38.79² =
  39. 39.31² =
  40. 40.61² =

Answer key

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

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