← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 9 · 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.A leapfrog list starts 8, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  2. 2.Leapfrog list (each number is the sum of the two before it): 8, 6, 14, 20, 34, 54, 88, 142, 230, 372. What is 11 × the 7th number?
  3. 3.Leapfrog list (each number is the sum of the two before it): 4, 4, 8, 12, 20, 32, 52, 84, 136, 220. What is 11 × the 7th number?
  4. 4.Leapfrog list (each number is the sum of the two before it): 2, 9, 11, 20, 31, 51, 82, 133, 215, 348. What is 11 × the 7th number?
  5. 5.Leapfrog list (each number is the sum of the two before it): 2, 3, 5, 8, 13, 21, 34, 55, 89, 144. What is 11 × the 7th number?
  6. 6.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?
  7. 7.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?
  8. 8.3 + 3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 =
  9. 9.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?
  10. 10.9 + 5 + 14 + 19 + 33 + 52 + 85 + 137 + 222 + 359 =
  11. 11.A leapfrog list starts 6, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  12. 12.5 + 1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 =
  13. 13.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?
  14. 14.9 + 2 + 11 + 13 + 24 + 37 + 61 + 98 + 159 + 257 =
  15. 15.6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 + 432 =
  16. 16.Leapfrog list (each number is the sum of the two before it): 8, 5, 13, 18, 31, 49, 80, 129, 209, 338. What is 11 × the 7th number?
  17. 17.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?
  18. 18.A leapfrog list starts 6, 9 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 5, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  20. 20.5 + 4 + 9 + 13 + 22 + 35 + 57 + 92 + 149 + 241 =
  21. 21.1 + 1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 =
  22. 22.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?
  23. 23.6 + 1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 =
  24. 24.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?
  25. 25.A leapfrog list starts 4, 2 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): 2, 8, 10, 18, 28, 46, 74, 120, 194, 314. What is 11 × the 7th number?
  27. 27.3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 + 335 =
  28. 28.5 + 2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 =
  29. 29.Leapfrog list (each number is the sum of the two before it): 3, 9, 12, 21, 33, 54, 87, 141, 228, 369. What is 11 × the 7th number?
  30. 30.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?
  31. 31.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?
  32. 32.A leapfrog list starts 6, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  33. 33.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?
  34. 34.3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 =
  35. 35.Leapfrog list (each number is the sum of the two before it): 7, 3, 10, 13, 23, 36, 59, 95, 154, 249. What is 11 × the 7th number?
  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, 8, 11, 19, 30, 49, 79, 128, 207, 335. What is 11 × the 7th number?
  38. 38.Leapfrog list (each number is the sum of the two before it): 5, 2, 7, 9, 16, 25, 41, 66, 107, 173. What is 11 × the 7th number?
  39. 39.Leapfrog list (each number is the sum of the two before it): 6, 5, 11, 16, 27, 43, 70, 113, 183, 296. What is 11 × the 7th number?
  40. 40.2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 + 246 =

Answer key

  1. 1232
  2. 968
  3. 572
  4. 902
  5. 374
  6. 1001
  7. 902
  8. 429
  9. 495
  10. 935
  11. 946
  12. 363
  13. 880
  14. 671
  15. 1122
  16. 880
  17. 792
  18. 1122
  19. 803
  20. 627
  21. 143
  22. 704
  23. 418
  24. 319
  25. 396
  26. 814
  27. 869
  28. 451
  29. 957
  30. 143
  31. 781
  32. 418
  33. 319
  34. 517
  35. 649
  36. 1023
  37. 869
  38. 451
  39. 770
  40. 638

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