← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 496 · 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. 1.4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 + 178 + 288 =
  2. 2.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?
  3. 3.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?
  4. 4.Leapfrog list (each number is the sum of the two before it): 2, 8, 10, 18, 28, 46, 74, 120, 194, 314. What is 11 × the 7th number?
  5. 5.A leapfrog list starts 3, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  6. 6.2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 =
  7. 7.6 + 5 + 11 + 16 + 27 + 43 + 70 + 113 + 183 + 296 =
  8. 8.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?
  9. 9.6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 + 246 + 398 =
  10. 10.3 + 3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 =
  11. 11.Leapfrog list (each number is the sum of the two before it): 8, 2, 10, 12, 22, 34, 56, 90, 146, 236. What is 11 × the 7th number?
  12. 12.9 + 9 + 18 + 27 + 45 + 72 + 117 + 189 + 306 + 495 =
  13. 13.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?
  14. 14.6 + 4 + 10 + 14 + 24 + 38 + 62 + 100 + 162 + 262 =
  15. 15.8 + 8 + 16 + 24 + 40 + 64 + 104 + 168 + 272 + 440 =
  16. 16.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?
  17. 17.Leapfrog list (each number is the sum of the two before it): 9, 5, 14, 19, 33, 52, 85, 137, 222, 359. What is 11 × the 7th number?
  18. 18.8 + 1 + 9 + 10 + 19 + 29 + 48 + 77 + 125 + 202 =
  19. 19.Leapfrog list (each number is the sum of the two before it): 2, 7, 9, 16, 25, 41, 66, 107, 173, 280. What is 11 × the 7th number?
  20. 20.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?
  21. 21.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?
  22. 22.Leapfrog list (each number is the sum of the two before it): 4, 1, 5, 6, 11, 17, 28, 45, 73, 118. What is 11 × the 7th number?
  23. 23.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?
  24. 24.Leapfrog list (each number is the sum of the two before it): 4, 9, 13, 22, 35, 57, 92, 149, 241, 390. What is 11 × the 7th number?
  25. 25.A leapfrog list starts 1, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  26. 26.8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 + 474 =
  27. 27.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?
  28. 28.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?
  29. 29.2 + 1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 =
  30. 30.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?
  31. 31.A leapfrog list starts 9, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  32. 32.3 + 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 =
  33. 33.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?
  34. 34.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?
  35. 35.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?
  36. 36.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?
  37. 37.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?
  38. 38.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?
  39. 39.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?
  40. 40.Leapfrog list (each number is the sum of the two before it): 5, 9, 14, 23, 37, 60, 97, 157, 254, 411. What is 11 × the 7th number?

Answer key

  1. 748
  2. 528
  3. 363
  4. 814
  5. 781
  6. 374
  7. 770
  8. 770
  9. 1034
  10. 429
  11. 616
  12. 1287
  13. 583
  14. 682
  15. 1144
  16. 396
  17. 935
  18. 528
  19. 726
  20. 638
  21. 803
  22. 308
  23. 1122
  24. 1012
  25. 847
  26. 1232
  27. 682
  28. 1001
  29. 198
  30. 143
  31. 1287
  32. 253
  33. 1012
  34. 484
  35. 814
  36. 506
  37. 660
  38. 495
  39. 363
  40. 1067

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