← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 470 · 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.Leapfrog list (each number is the sum of the two before it): 7, 7, 14, 21, 35, 56, 91, 147, 238, 385. What is 11 × the 7th number?
  3. 3.1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 + 225 =
  4. 4.4 + 3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 =
  5. 5.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?
  6. 6.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?
  7. 7.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?
  8. 8.3 + 3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 =
  9. 9.A leapfrog list starts 1, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  10. 10.6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 + 246 + 398 =
  11. 11.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?
  12. 12.3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 =
  13. 13.A leapfrog list starts 6, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  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. 15.5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 + 191 + 309 =
  16. 16.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?
  17. 17.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?
  18. 18.A leapfrog list starts 8, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  19. 19.Leapfrog list (each number is the sum of the two before it): 7, 6, 13, 19, 32, 51, 83, 134, 217, 351. What is 11 × the 7th number?
  20. 20.2 + 1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 =
  21. 21.5 + 5 + 10 + 15 + 25 + 40 + 65 + 105 + 170 + 275 =
  22. 22.A leapfrog list starts 7, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  23. 23.2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 =
  24. 24.Leapfrog list (each number is the sum of the two before it): 8, 7, 15, 22, 37, 59, 96, 155, 251, 406. What is 11 × the 7th number?
  25. 25.A leapfrog list starts 1, 6 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): 9, 8, 17, 25, 42, 67, 109, 176, 285, 461. What is 11 × the 7th number?
  27. 27.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?
  28. 28.7 + 5 + 12 + 17 + 29 + 46 + 75 + 121 + 196 + 317 =
  29. 29.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?
  30. 30.Leapfrog list (each number is the sum of the two before it): 3, 2, 5, 7, 12, 19, 31, 50, 81, 131. What is 11 × the 7th number?
  31. 31.5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 + 343 =
  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.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?
  34. 34.1 + 9 + 10 + 19 + 29 + 48 + 77 + 125 + 202 + 327 =
  35. 35.A leapfrog list starts 7, 7 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): 3, 8, 11, 19, 30, 49, 79, 128, 207, 335. What is 11 × the 7th number?
  37. 37.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?
  38. 38.5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 + 254 + 411 =
  39. 39.2 + 2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 =
  40. 40.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?

Answer key

  1. 880
  2. 1001
  3. 583
  4. 484
  5. 418
  6. 759
  7. 715
  8. 429
  9. 671
  10. 1034
  11. 671
  12. 517
  13. 1034
  14. 913
  15. 803
  16. 484
  17. 1177
  18. 704
  19. 913
  20. 198
  21. 715
  22. 649
  23. 374
  24. 1056
  25. 583
  26. 1199
  27. 539
  28. 825
  29. 1177
  30. 341
  31. 891
  32. 528
  33. 231
  34. 847
  35. 1001
  36. 869
  37. 924
  38. 1067
  39. 286
  40. 957

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