← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 70 · 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.Leapfrog list (each number is the sum of the two before it): 5, 3, 8, 11, 19, 30, 49, 79, 128, 207. What is 11 × the 7th number?
  2. 2.Leapfrog list (each number is the sum of the two before it): 2, 1, 3, 4, 7, 11, 18, 29, 47, 76. What is 11 × the 7th number?
  3. 3.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?
  4. 4.A leapfrog list starts 7, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  5. 5.Leapfrog list (each number is the sum of the two before it): 3, 5, 8, 13, 21, 34, 55, 89, 144, 233. What is 11 × the 7th number?
  6. 6.3 + 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 =
  7. 7.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
  8. 8.8 + 4 + 12 + 16 + 28 + 44 + 72 + 116 + 188 + 304 =
  9. 9.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?
  10. 10.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?
  11. 11.A leapfrog list starts 6, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  12. 12.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?
  13. 13.Leapfrog list (each number is the sum of the two before it): 9, 8, 17, 25, 42, 67, 109, 176, 285, 461. What is 11 × the 7th number?
  14. 14.8 + 7 + 15 + 22 + 37 + 59 + 96 + 155 + 251 + 406 =
  15. 15.8 + 5 + 13 + 18 + 31 + 49 + 80 + 129 + 209 + 338 =
  16. 16.1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 =
  17. 17.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?
  18. 18.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?
  19. 19.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?
  20. 20.Leapfrog list (each number is the sum of the two before it): 1, 4, 5, 9, 14, 23, 37, 60, 97, 157. What is 11 × the 7th number?
  21. 21.A leapfrog list starts 9, 9 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 3, 8 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): 7, 9, 16, 25, 41, 66, 107, 173, 280, 453. What is 11 × the 7th number?
  24. 24.A leapfrog list starts 5, 8 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 2, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  26. 26.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?
  27. 27.Leapfrog list (each number is the sum of the two before it): 6, 3, 9, 12, 21, 33, 54, 87, 141, 228. What is 11 × the 7th number?
  28. 28.Leapfrog list (each number is the sum of the two before it): 9, 6, 15, 21, 36, 57, 93, 150, 243, 393. What is 11 × the 7th number?
  29. 29.6 + 3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 =
  30. 30.9 + 1 + 10 + 11 + 21 + 32 + 53 + 85 + 138 + 223 =
  31. 31.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?
  32. 32.7 + 4 + 11 + 15 + 26 + 41 + 67 + 108 + 175 + 283 =
  33. 33.3 + 2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 =
  34. 34.6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 + 432 =
  35. 35.3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 =
  36. 36.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?
  37. 37.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?
  38. 38.2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 =
  39. 39.A leapfrog list starts 7, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  40. 40.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?

Answer key

  1. 539
  2. 198
  3. 671
  4. 825
  5. 605
  6. 253
  7. 781
  8. 792
  9. 902
  10. 1001
  11. 858
  12. 924
  13. 1199
  14. 1056
  15. 880
  16. 319
  17. 814
  18. 781
  19. 451
  20. 407
  21. 1287
  22. 869
  23. 1177
  24. 979
  25. 638
  26. 704
  27. 594
  28. 1023
  29. 594
  30. 583
  31. 869
  32. 737
  33. 341
  34. 1122
  35. 693
  36. 528
  37. 308
  38. 374
  39. 561
  40. 374

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