← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 558 · 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. 1.3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 + 335 =
  2. 2.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?
  3. 3.6 + 5 + 11 + 16 + 27 + 43 + 70 + 113 + 183 + 296 =
  4. 4.Leapfrog list (each number is the sum of the two before it): 8, 4, 12, 16, 28, 44, 72, 116, 188, 304. What is 11 × the 7th number?
  5. 5.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?
  6. 6.3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 + 369 =
  7. 7.Leapfrog list (each number is the sum of the two before it): 6, 7, 13, 20, 33, 53, 86, 139, 225, 364. What is 11 × the 7th number?
  8. 8.A leapfrog list starts 7, 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 + 3 + 12 + 15 + 27 + 42 + 69 + 111 + 180 + 291 =
  10. 10.6 + 1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 =
  11. 11.Leapfrog list (each number is the sum of the two before it): 3, 3, 6, 9, 15, 24, 39, 63, 102, 165. What is 11 × the 7th number?
  12. 12.A leapfrog list starts 5, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  13. 13.2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 + 178 =
  14. 14.5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 + 343 =
  15. 15.Leapfrog list (each number is the sum of the two before it): 8, 3, 11, 14, 25, 39, 64, 103, 167, 270. What is 11 × the 7th number?
  16. 16.Leapfrog list (each number is the sum of the two before it): 5, 4, 9, 13, 22, 35, 57, 92, 149, 241. What is 11 × the 7th number?
  17. 17.6 + 6 + 12 + 18 + 30 + 48 + 78 + 126 + 204 + 330 =
  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): 4, 6, 10, 16, 26, 42, 68, 110, 178, 288. What is 11 × the 7th number?
  20. 20.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?
  21. 21.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?
  22. 22.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?
  23. 23.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?
  24. 24.9 + 8 + 17 + 25 + 42 + 67 + 109 + 176 + 285 + 461 =
  25. 25.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?
  26. 26.A leapfrog list starts 1, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  27. 27.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?
  28. 28.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?
  29. 29.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?
  30. 30.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?
  31. 31.A leapfrog list starts 2, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  32. 32.1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 =
  33. 33.3 + 2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 =
  34. 34.5 + 4 + 9 + 13 + 22 + 35 + 57 + 92 + 149 + 241 =
  35. 35.2 + 9 + 11 + 20 + 31 + 51 + 82 + 133 + 215 + 348 =
  36. 36.1 + 1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 =
  37. 37.Leapfrog list (each number is the sum of the two before it): 7, 8, 15, 23, 38, 61, 99, 160, 259, 419. What is 11 × the 7th number?
  38. 38.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?
  39. 39.5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 + 191 + 309 =
  40. 40.1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 =

Answer key

  1. 869
  2. 1056
  3. 770
  4. 792
  5. 1232
  6. 957
  7. 946
  8. 737
  9. 759
  10. 418
  11. 429
  12. 451
  13. 462
  14. 891
  15. 704
  16. 627
  17. 858
  18. 704
  19. 748
  20. 363
  21. 528
  22. 770
  23. 627
  24. 1199
  25. 715
  26. 319
  27. 935
  28. 979
  29. 924
  30. 1001
  31. 374
  32. 231
  33. 341
  34. 627
  35. 902
  36. 143
  37. 1089
  38. 858
  39. 803
  40. 319

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