← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 102 · 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.Leapfrog list (each number is the sum of the two before it): 5, 8, 13, 21, 34, 55, 89, 144, 233, 377. What is 11 × the 7th number?
  2. 2.1 + 9 + 10 + 19 + 29 + 48 + 77 + 125 + 202 + 327 =
  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): 9, 4, 13, 17, 30, 47, 77, 124, 201, 325. What is 11 × the 7th number?
  5. 5.Leapfrog list (each number is the sum of the two before it): 1, 6, 7, 13, 20, 33, 53, 86, 139, 225. What is 11 × the 7th number?
  6. 6.A leapfrog list starts 6, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  7. 7.7 + 3 + 10 + 13 + 23 + 36 + 59 + 95 + 154 + 249 =
  8. 8.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?
  9. 9.9 + 2 + 11 + 13 + 24 + 37 + 61 + 98 + 159 + 257 =
  10. 10.4 + 1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 =
  11. 11.8 + 7 + 15 + 22 + 37 + 59 + 96 + 155 + 251 + 406 =
  12. 12.Leapfrog list (each number is the sum of the two before it): 7, 9, 16, 25, 41, 66, 107, 173, 280, 453. 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): 5, 1, 6, 7, 13, 20, 33, 53, 86, 139. What is 11 × the 7th number?
  15. 15.1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 =
  16. 16.A leapfrog list starts 3, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  17. 17.4 + 4 + 8 + 12 + 20 + 32 + 52 + 84 + 136 + 220 =
  18. 18.Leapfrog list (each number is the sum of the two before it): 1, 1, 2, 3, 5, 8, 13, 21, 34, 55. What is 11 × the 7th number?
  19. 19.8 + 5 + 13 + 18 + 31 + 49 + 80 + 129 + 209 + 338 =
  20. 20.A leapfrog list starts 5, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  21. 21.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?
  22. 22.Leapfrog list (each number is the sum of the two before it): 5, 2, 7, 9, 16, 25, 41, 66, 107, 173. What is 11 × the 7th number?
  23. 23.Leapfrog list (each number is the sum of the two before it): 1, 3, 4, 7, 11, 18, 29, 47, 76, 123. What is 11 × the 7th number?
  24. 24.4 + 3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 =
  25. 25.7 + 1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 =
  26. 26.Leapfrog list (each number is the sum of the two before it): 1, 2, 3, 5, 8, 13, 21, 34, 55, 89. What is 11 × the 7th number?
  27. 27.Leapfrog list (each number is the sum of the two before it): 8, 9, 17, 26, 43, 69, 112, 181, 293, 474. What is 11 × the 7th number?
  28. 28.A leapfrog list starts 7, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  29. 29.A leapfrog list starts 4, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  30. 30.Leapfrog list (each number is the sum of the two before it): 5, 6, 11, 17, 28, 45, 73, 118, 191, 309. What is 11 × the 7th number?
  31. 31.3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 + 233 =
  32. 32.4 + 8 + 12 + 20 + 32 + 52 + 84 + 136 + 220 + 356 =
  33. 33.8 + 1 + 9 + 10 + 19 + 29 + 48 + 77 + 125 + 202 =
  34. 34.A leapfrog list starts 8, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  35. 35.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?
  36. 36.A leapfrog list starts 9, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  37. 37.9 + 7 + 16 + 23 + 39 + 62 + 101 + 163 + 264 + 427 =
  38. 38.2 + 2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 =
  39. 39.A leapfrog list starts 3, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  40. 40.9 + 3 + 12 + 15 + 27 + 42 + 69 + 111 + 180 + 291 =

Answer key

  1. 979
  2. 847
  3. 1122
  4. 847
  5. 583
  6. 858
  7. 649
  8. 517
  9. 671
  10. 308
  11. 1056
  12. 1177
  13. 407
  14. 363
  15. 407
  16. 693
  17. 572
  18. 143
  19. 880
  20. 627
  21. 418
  22. 451
  23. 319
  24. 484
  25. 473
  26. 231
  27. 1232
  28. 825
  29. 660
  30. 803
  31. 605
  32. 924
  33. 528
  34. 792
  35. 495
  36. 583
  37. 1111
  38. 286
  39. 253
  40. 759

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