← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 97 · 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 4, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  2. 2.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?
  3. 3.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?
  4. 4.5 + 5 + 10 + 15 + 25 + 40 + 65 + 105 + 170 + 275 =
  5. 5.4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 + 254 =
  6. 6.2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 + 280 =
  7. 7.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?
  8. 8.8 + 4 + 12 + 16 + 28 + 44 + 72 + 116 + 188 + 304 =
  9. 9.A leapfrog list starts 4, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  10. 10.8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 + 474 =
  11. 11.1 + 9 + 10 + 19 + 29 + 48 + 77 + 125 + 202 + 327 =
  12. 12.2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 + 314 =
  13. 13.Leapfrog list (each number is the sum of the two before it): 2, 2, 4, 6, 10, 16, 26, 42, 68, 110. What is 11 × the 7th number?
  14. 14.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?
  15. 15.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?
  16. 16.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?
  17. 17.2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 =
  18. 18.3 + 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 =
  19. 19.1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 =
  20. 20.A leapfrog list starts 4, 6 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): 1, 6, 7, 13, 20, 33, 53, 86, 139, 225. What is 11 × the 7th number?
  22. 22.Leapfrog list (each number is the sum of the two before it): 2, 4, 6, 10, 16, 26, 42, 68, 110, 178. What is 11 × the 7th number?
  23. 23.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?
  24. 24.3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 =
  25. 25.1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 =
  26. 26.7 + 3 + 10 + 13 + 23 + 36 + 59 + 95 + 154 + 249 =
  27. 27.6 + 3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 =
  28. 28.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?
  29. 29.A leapfrog list starts 3, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  30. 30.4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 + 322 =
  31. 31.2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 + 178 =
  32. 32.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?
  33. 33.1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 =
  34. 34.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?
  35. 35.4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 + 178 + 288 =
  36. 36.5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 + 233 + 377 =
  37. 37.5 + 2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 =
  38. 38.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?
  39. 39.Leapfrog list (each number is the sum of the two before it): 7, 2, 9, 11, 20, 31, 51, 82, 133, 215. What is 11 × the 7th number?
  40. 40.Leapfrog list (each number is the sum of the two before it): 1, 9, 10, 19, 29, 48, 77, 125, 202, 327. What is 11 × the 7th number?

Answer key

  1. 572
  2. 770
  3. 528
  4. 715
  5. 660
  6. 726
  7. 506
  8. 792
  9. 308
  10. 1232
  11. 847
  12. 814
  13. 286
  14. 1177
  15. 847
  16. 638
  17. 550
  18. 253
  19. 407
  20. 748
  21. 583
  22. 462
  23. 792
  24. 693
  25. 759
  26. 649
  27. 594
  28. 495
  29. 869
  30. 836
  31. 462
  32. 429
  33. 231
  34. 583
  35. 748
  36. 979
  37. 451
  38. 495
  39. 561
  40. 847

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