← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 1 · 40 questions
TalentJR

The trick (Seventh times eleven): A leapfrog list: start with two numbers, then each number is the sum of the two before it, up to 10 numbers. Find the 7th number. Multiply it by 11 (the number with a 0 on the end, plus the number): that is the total of all 10.

NameDateTime takenScore ___ / 40
  1. 1.A leapfrog list starts 6, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  2. 2.A leapfrog list starts 1, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  3. 3.6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 + 432 =
  4. 4.Leapfrog list (each number is the sum of the two before it): 4, 4, 8, 12, 20, 32, 52, 84, 136, 220. What is 11 × the 7th number?
  5. 5.5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 + 191 + 309 =
  6. 6.8 + 5 + 13 + 18 + 31 + 49 + 80 + 129 + 209 + 338 =
  7. 7.4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 + 322 =
  8. 8.A leapfrog list starts 9, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  9. 9.A leapfrog list starts 2, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  10. 10.7 + 4 + 11 + 15 + 26 + 41 + 67 + 108 + 175 + 283 =
  11. 11.Leapfrog list (each number is the sum of the two before it): 4, 2, 6, 8, 14, 22, 36, 58, 94, 152. What is 11 × the 7th number?
  12. 12.Leapfrog list (each number is the sum of the two before it): 6, 1, 7, 8, 15, 23, 38, 61, 99, 160. What is 11 × the 7th number?
  13. 13.A leapfrog list starts 1, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  14. 14.Leapfrog list (each number is the sum of the two before it): 8, 5, 13, 18, 31, 49, 80, 129, 209, 338. What is 11 × the 7th number?
  15. 15.A leapfrog list starts 3, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  16. 16.Leapfrog list (each number is the sum of the two before it): 2, 9, 11, 20, 31, 51, 82, 133, 215, 348. What is 11 × the 7th number?
  17. 17.1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 =
  18. 18.4 + 3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 =
  19. 19.Leapfrog list (each number is the sum of the two before it): 9, 3, 12, 15, 27, 42, 69, 111, 180, 291. What is 11 × the 7th number?
  20. 20.5 + 2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 =
  21. 21.2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 =
  22. 22.A leapfrog list starts 7, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  23. 23.2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 + 246 =
  24. 24.A leapfrog list starts 8, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  25. 25.A leapfrog list starts 4, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  26. 26.Leapfrog list (each number is the sum of the two before it): 1, 5, 6, 11, 17, 28, 45, 73, 118, 191. What is 11 × the 7th number?
  27. 27.Leapfrog list (each number is the sum of the two before it): 5, 1, 6, 7, 13, 20, 33, 53, 86, 139. What is 11 × the 7th number?
  28. 28.A leapfrog list starts 4, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  29. 29.5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 + 254 + 411 =
  30. 30.9 + 5 + 14 + 19 + 33 + 52 + 85 + 137 + 222 + 359 =
  31. 31.9 + 7 + 16 + 23 + 39 + 62 + 101 + 163 + 264 + 427 =
  32. 32.4 + 1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 =
  33. 33.1 + 1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 =
  34. 34.Leapfrog list (each number is the sum of the two before it): 6, 4, 10, 14, 24, 38, 62, 100, 162, 262. What is 11 × the 7th number?
  35. 35.3 + 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 =
  36. 36.3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 =
  37. 37.A leapfrog list starts 7, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  38. 38.5 + 1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 =
  39. 39.9 + 1 + 10 + 11 + 21 + 32 + 53 + 85 + 138 + 223 =
  40. 40.Leapfrog list (each number is the sum of the two before it): 4, 3, 7, 10, 17, 27, 44, 71, 115, 186. What is 11 × the 7th number?

Answer key

  1. 418
  2. 231
  3. 1122
  4. 572
  5. 803
  6. 880
  7. 836
  8. 671
  9. 286
  10. 737
  11. 396
  12. 418
  13. 407
  14. 880
  15. 517
  16. 902
  17. 407
  18. 484
  19. 759
  20. 451
  21. 374
  22. 913
  23. 638
  24. 1056
  25. 1012
  26. 495
  27. 363
  28. 484
  29. 1067
  30. 935
  31. 1111
  32. 308
  33. 143
  34. 682
  35. 253
  36. 517
  37. 1177
  38. 363
  39. 583
  40. 484

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