← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 566 · 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 + 6 + 14 + 20 + 34 + 54 + 88 + 142 + 230 + 372 =
  2. 2.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?
  3. 3.3 + 2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 =
  4. 4.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?
  5. 5.A leapfrog list starts 2, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  6. 6.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?
  7. 7.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?
  8. 8.Leapfrog list (each number is the sum of the two before it): 6, 6, 12, 18, 30, 48, 78, 126, 204, 330. What is 11 × the 7th number?
  9. 9.A leapfrog list starts 3, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  10. 10.4 + 4 + 8 + 12 + 20 + 32 + 52 + 84 + 136 + 220 =
  11. 11.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?
  12. 12.Leapfrog list (each number is the sum of the two before it): 9, 7, 16, 23, 39, 62, 101, 163, 264, 427. What is 11 × the 7th number?
  13. 13.8 + 5 + 13 + 18 + 31 + 49 + 80 + 129 + 209 + 338 =
  14. 14.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?
  15. 15.Leapfrog list (each number is the sum of the two before it): 1, 3, 4, 7, 11, 18, 29, 47, 76, 123. What is 11 × the 7th number?
  16. 16.A leapfrog list starts 8, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  17. 17.2 + 1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 =
  18. 18.5 + 2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 =
  19. 19.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?
  20. 20.A leapfrog list starts 9, 1 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 4, 8 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 1, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  23. 23.7 + 7 + 14 + 21 + 35 + 56 + 91 + 147 + 238 + 385 =
  24. 24.7 + 6 + 13 + 19 + 32 + 51 + 83 + 134 + 217 + 351 =
  25. 25.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?
  26. 26.Leapfrog list (each number is the sum of the two before it): 6, 8, 14, 22, 36, 58, 94, 152, 246, 398. What is 11 × the 7th number?
  27. 27.A leapfrog list starts 2, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  28. 28.2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 =
  29. 29.Leapfrog list (each number is the sum of the two before it): 9, 1, 10, 11, 21, 32, 53, 85, 138, 223. What is 11 × the 7th number?
  30. 30.A leapfrog list starts 8, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  31. 31.3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 + 335 =
  32. 32.3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 =
  33. 33.A leapfrog list starts 8, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  34. 34.6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 + 432 =
  35. 35.A leapfrog list starts 9, 4 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 9, 6 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): 3, 1, 4, 5, 9, 14, 23, 37, 60, 97. What is 11 × the 7th number?
  38. 38.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?
  39. 39.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?
  40. 40.Leapfrog list (each number is the sum of the two before it): 9, 4, 13, 17, 30, 47, 77, 124, 201, 325. What is 11 × the 7th number?

Answer key

  1. 968
  2. 660
  3. 341
  4. 429
  5. 726
  6. 462
  7. 418
  8. 858
  9. 605
  10. 572
  11. 231
  12. 1111
  13. 880
  14. 814
  15. 319
  16. 616
  17. 198
  18. 451
  19. 198
  20. 583
  21. 924
  22. 495
  23. 1001
  24. 913
  25. 935
  26. 1034
  27. 902
  28. 374
  29. 583
  30. 528
  31. 869
  32. 693
  33. 792
  34. 1122
  35. 847
  36. 1023
  37. 253
  38. 374
  39. 913
  40. 847

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