← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 98 · 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, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  2. 2.2 + 1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 =
  3. 3.A leapfrog list starts 5, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  4. 4.A leapfrog list starts 3, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  5. 5.Leapfrog list (each number is the sum of the two before it): 4, 8, 12, 20, 32, 52, 84, 136, 220, 356. What is 11 × the 7th number?
  6. 6.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?
  7. 7.7 + 1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 =
  8. 8.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?
  9. 9.5 + 2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 =
  10. 10.9 + 7 + 16 + 23 + 39 + 62 + 101 + 163 + 264 + 427 =
  11. 11.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?
  12. 12.4 + 2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 =
  13. 13.6 + 2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 =
  14. 14.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?
  15. 15.A leapfrog list starts 5, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  16. 16.5 + 4 + 9 + 13 + 22 + 35 + 57 + 92 + 149 + 241 =
  17. 17.1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 + 225 =
  18. 18.A leapfrog list starts 8, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  19. 19.1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 =
  20. 20.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?
  21. 21.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?
  22. 22.A leapfrog list starts 2, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  23. 23.6 + 5 + 11 + 16 + 27 + 43 + 70 + 113 + 183 + 296 =
  24. 24.5 + 5 + 10 + 15 + 25 + 40 + 65 + 105 + 170 + 275 =
  25. 25.Leapfrog list (each number is the sum of the two before it): 9, 6, 15, 21, 36, 57, 93, 150, 243, 393. What is 11 × the 7th number?
  26. 26.4 + 8 + 12 + 20 + 32 + 52 + 84 + 136 + 220 + 356 =
  27. 27.A leapfrog list starts 6, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  28. 28.A leapfrog list starts 2, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  29. 29.2 + 2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 =
  30. 30.Leapfrog list (each number is the sum of the two before it): 6, 2, 8, 10, 18, 28, 46, 74, 120, 194. What is 11 × the 7th number?
  31. 31.A leapfrog list starts 5, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  32. 32.Leapfrog list (each number is the sum of the two before it): 8, 1, 9, 10, 19, 29, 48, 77, 125, 202. What is 11 × the 7th number?
  33. 33.3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 + 335 =
  34. 34.Leapfrog list (each number is the sum of the two before it): 2, 6, 8, 14, 22, 36, 58, 94, 152, 246. What is 11 × the 7th number?
  35. 35.A leapfrog list starts 3, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  36. 36.Leapfrog list (each number is the sum of the two before it): 7, 4, 11, 15, 26, 41, 67, 108, 175, 283. What is 11 × the 7th number?
  37. 37.Leapfrog list (each number is the sum of the two before it): 2, 4, 6, 10, 16, 26, 42, 68, 110, 178. What is 11 × the 7th number?
  38. 38.Leapfrog list (each number is the sum of the two before it): 6, 9, 15, 24, 39, 63, 102, 165, 267, 432. What is 11 × the 7th number?
  39. 39.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?
  40. 40.4 + 9 + 13 + 22 + 35 + 57 + 92 + 149 + 241 + 390 =

Answer key

  1. 770
  2. 198
  3. 539
  4. 957
  5. 924
  6. 660
  7. 473
  8. 451
  9. 451
  10. 1111
  11. 143
  12. 396
  13. 506
  14. 913
  15. 363
  16. 627
  17. 583
  18. 968
  19. 319
  20. 484
  21. 517
  22. 198
  23. 770
  24. 715
  25. 1023
  26. 924
  27. 506
  28. 550
  29. 286
  30. 506
  31. 715
  32. 528
  33. 869
  34. 638
  35. 341
  36. 737
  37. 462
  38. 1122
  39. 418
  40. 1012

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