← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 601 · 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 3, 2 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): 6, 2, 8, 10, 18, 28, 46, 74, 120, 194. What is 11 × the 7th number?
  3. 3.6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 + 225 + 364 =
  4. 4.7 + 3 + 10 + 13 + 23 + 36 + 59 + 95 + 154 + 249 =
  5. 5.8 + 2 + 10 + 12 + 22 + 34 + 56 + 90 + 146 + 236 =
  6. 6.3 + 2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 =
  7. 7.6 + 6 + 12 + 18 + 30 + 48 + 78 + 126 + 204 + 330 =
  8. 8.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?
  9. 9.1 + 9 + 10 + 19 + 29 + 48 + 77 + 125 + 202 + 327 =
  10. 10.8 + 3 + 11 + 14 + 25 + 39 + 64 + 103 + 167 + 270 =
  11. 11.9 + 8 + 17 + 25 + 42 + 67 + 109 + 176 + 285 + 461 =
  12. 12.1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 =
  13. 13.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?
  14. 14.A leapfrog list starts 5, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  15. 15.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?
  16. 16.4 + 2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 =
  17. 17.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?
  18. 18.3 + 3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 =
  19. 19.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?
  20. 20.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?
  21. 21.3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 + 335 =
  22. 22.1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 =
  23. 23.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?
  24. 24.A leapfrog list starts 3, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  25. 25.Leapfrog list (each number is the sum of the two before it): 9, 9, 18, 27, 45, 72, 117, 189, 306, 495. What is 11 × the 7th number?
  26. 26.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
  27. 27.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?
  28. 28.5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 + 254 + 411 =
  29. 29.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?
  30. 30.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?
  31. 31.Leapfrog list (each number is the sum of the two before it): 9, 3, 12, 15, 27, 42, 69, 111, 180, 291. What is 11 × the 7th number?
  32. 32.1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 + 259 =
  33. 33.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?
  34. 34.6 + 2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 =
  35. 35.8 + 7 + 15 + 22 + 37 + 59 + 96 + 155 + 251 + 406 =
  36. 36.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?
  37. 37.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?
  38. 38.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?
  39. 39.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?
  40. 40.9 + 2 + 11 + 13 + 24 + 37 + 61 + 98 + 159 + 257 =

Answer key

  1. 341
  2. 506
  3. 946
  4. 649
  5. 616
  6. 341
  7. 858
  8. 572
  9. 847
  10. 704
  11. 1199
  12. 319
  13. 924
  14. 1067
  15. 583
  16. 396
  17. 880
  18. 429
  19. 715
  20. 616
  21. 869
  22. 759
  23. 528
  24. 517
  25. 1287
  26. 781
  27. 704
  28. 1067
  29. 1067
  30. 231
  31. 759
  32. 671
  33. 968
  34. 506
  35. 1056
  36. 847
  37. 858
  38. 319
  39. 770
  40. 671

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