← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 206 · 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. 1.8 + 5 + 13 + 18 + 31 + 49 + 80 + 129 + 209 + 338 =
  2. 2.A leapfrog list starts 4, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  3. 3.2 + 1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 =
  4. 4.4 + 1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 =
  5. 5.3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 + 233 =
  6. 6.6 + 2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 =
  7. 7.3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 =
  8. 8.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?
  9. 9.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?
  10. 10.9 + 8 + 17 + 25 + 42 + 67 + 109 + 176 + 285 + 461 =
  11. 11.A leapfrog list starts 2, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  12. 12.2 + 2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 =
  13. 13.Leapfrog list (each number is the sum of the two before it): 9, 2, 11, 13, 24, 37, 61, 98, 159, 257. What is 11 × the 7th number?
  14. 14.Leapfrog list (each number is the sum of the two before it): 4, 5, 9, 14, 23, 37, 60, 97, 157, 254. What is 11 × the 7th number?
  15. 15.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?
  16. 16.4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 + 178 + 288 =
  17. 17.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?
  18. 18.A leapfrog list starts 1, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  19. 19.A leapfrog list starts 8, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  20. 20.7 + 6 + 13 + 19 + 32 + 51 + 83 + 134 + 217 + 351 =
  21. 21.Leapfrog list (each number is the sum of the two before it): 2, 2, 4, 6, 10, 16, 26, 42, 68, 110. What is 11 × the 7th number?
  22. 22.Leapfrog list (each number is the sum of the two before it): 3, 1, 4, 5, 9, 14, 23, 37, 60, 97. What is 11 × the 7th number?
  23. 23.5 + 2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 =
  24. 24.A leapfrog list starts 1, 1 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 2, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  26. 26.A leapfrog list starts 2, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  27. 27.1 + 1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 =
  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. 29.2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 + 246 =
  30. 30.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?
  31. 31.2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 + 314 =
  32. 32.Leapfrog list (each number is the sum of the two before it): 5, 5, 10, 15, 25, 40, 65, 105, 170, 275. What is 11 × the 7th number?
  33. 33.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?
  34. 34.Leapfrog list (each number is the sum of the two before it): 4, 7, 11, 18, 29, 47, 76, 123, 199, 322. What is 11 × the 7th number?
  35. 35.Leapfrog list (each number is the sum of the two before it): 7, 2, 9, 11, 20, 31, 51, 82, 133, 215. What is 11 × the 7th number?
  36. 36.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?
  37. 37.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?
  38. 38.Leapfrog list (each number is the sum of the two before it): 7, 1, 8, 9, 17, 26, 43, 69, 112, 181. What is 11 × the 7th number?
  39. 39.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?
  40. 40.5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 + 191 + 309 =

Answer key

  1. 880
  2. 748
  3. 198
  4. 308
  5. 605
  6. 506
  7. 517
  8. 1012
  9. 638
  10. 1199
  11. 814
  12. 286
  13. 671
  14. 660
  15. 363
  16. 748
  17. 506
  18. 495
  19. 880
  20. 913
  21. 286
  22. 253
  23. 451
  24. 143
  25. 198
  26. 462
  27. 143
  28. 484
  29. 638
  30. 924
  31. 814
  32. 715
  33. 979
  34. 836
  35. 561
  36. 407
  37. 143
  38. 473
  39. 1056
  40. 803

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