← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 850 · 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 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 =
  2. 2.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?
  3. 3.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?
  4. 4.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?
  5. 5.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?
  6. 6.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?
  7. 7.Leapfrog list (each number is the sum of the two before it): 9, 2, 11, 13, 24, 37, 61, 98, 159, 257. What is 11 × the 7th number?
  8. 8.2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 + 280 =
  9. 9.A leapfrog list starts 4, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  10. 10.A leapfrog list starts 9, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  11. 11.5 + 3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 =
  12. 12.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?
  13. 13.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?
  14. 14.9 + 5 + 14 + 19 + 33 + 52 + 85 + 137 + 222 + 359 =
  15. 15.8 + 6 + 14 + 20 + 34 + 54 + 88 + 142 + 230 + 372 =
  16. 16.8 + 2 + 10 + 12 + 22 + 34 + 56 + 90 + 146 + 236 =
  17. 17.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?
  18. 18.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?
  19. 19.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?
  20. 20.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?
  21. 21.1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 + 225 =
  22. 22.A leapfrog list starts 1, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  23. 23.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?
  24. 24.2 + 1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 =
  25. 25.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?
  26. 26.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?
  27. 27.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?
  28. 28.A leapfrog list starts 3, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  29. 29.6 + 4 + 10 + 14 + 24 + 38 + 62 + 100 + 162 + 262 =
  30. 30.1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 + 259 =
  31. 31.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?
  32. 32.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?
  33. 33.Leapfrog list (each number is the sum of the two before it): 6, 9, 15, 24, 39, 63, 102, 165, 267, 432. What is 11 × the 7th number?
  34. 34.A leapfrog list starts 6, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  35. 35.Leapfrog list (each number is the sum of the two before it): 5, 6, 11, 17, 28, 45, 73, 118, 191, 309. What is 11 × the 7th number?
  36. 36.A leapfrog list starts 6, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  37. 37.6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 + 432 =
  38. 38.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?
  39. 39.Leapfrog list (each number is the sum of the two before it): 4, 1, 5, 6, 11, 17, 28, 45, 73, 118. What is 11 × the 7th number?
  40. 40.Leapfrog list (each number is the sum of the two before it): 6, 4, 10, 14, 24, 38, 62, 100, 162, 262. What is 11 × the 7th number?

Answer key

  1. 517
  2. 143
  3. 770
  4. 1034
  5. 924
  6. 374
  7. 671
  8. 726
  9. 484
  10. 1111
  11. 539
  12. 253
  13. 451
  14. 935
  15. 968
  16. 616
  17. 528
  18. 979
  19. 517
  20. 869
  21. 583
  22. 231
  23. 429
  24. 198
  25. 374
  26. 759
  27. 1232
  28. 253
  29. 682
  30. 671
  31. 418
  32. 319
  33. 1122
  34. 594
  35. 803
  36. 1034
  37. 1122
  38. 968
  39. 308
  40. 682

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