← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 650 · 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. 1.1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 =
  2. 2.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?
  3. 3.8 + 5 + 13 + 18 + 31 + 49 + 80 + 129 + 209 + 338 =
  4. 4.7 + 5 + 12 + 17 + 29 + 46 + 75 + 121 + 196 + 317 =
  5. 5.A leapfrog list starts 1, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  6. 6.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?
  7. 7.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
  8. 8.A leapfrog list starts 5, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  9. 9.7 + 3 + 10 + 13 + 23 + 36 + 59 + 95 + 154 + 249 =
  10. 10.1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 + 259 =
  11. 11.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?
  12. 12.7 + 1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 =
  13. 13.3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 =
  14. 14.4 + 3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 =
  15. 15.Leapfrog list (each number is the sum of the two before it): 9, 1, 10, 11, 21, 32, 53, 85, 138, 223. What is 11 × the 7th number?
  16. 16.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?
  17. 17.Leapfrog list (each number is the sum of the two before it): 2, 5, 7, 12, 19, 31, 50, 81, 131, 212. What is 11 × the 7th number?
  18. 18.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?
  19. 19.9 + 3 + 12 + 15 + 27 + 42 + 69 + 111 + 180 + 291 =
  20. 20.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?
  21. 21.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?
  22. 22.3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 =
  23. 23.A leapfrog list starts 3, 9 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 4, 9 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): 7, 1, 8, 9, 17, 26, 43, 69, 112, 181. What is 11 × the 7th number?
  26. 26.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?
  27. 27.2 + 2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 =
  28. 28.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?
  29. 29.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?
  30. 30.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?
  31. 31.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?
  32. 32.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?
  33. 33.1 + 9 + 10 + 19 + 29 + 48 + 77 + 125 + 202 + 327 =
  34. 34.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?
  35. 35.Leapfrog list (each number is the sum of the two before it): 2, 7, 9, 16, 25, 41, 66, 107, 173, 280. What is 11 × the 7th number?
  36. 36.8 + 1 + 9 + 10 + 19 + 29 + 48 + 77 + 125 + 202 =
  37. 37.8 + 7 + 15 + 22 + 37 + 59 + 96 + 155 + 251 + 406 =
  38. 38.8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 + 474 =
  39. 39.4 + 4 + 8 + 12 + 20 + 32 + 52 + 84 + 136 + 220 =
  40. 40.A leapfrog list starts 9, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?

Answer key

  1. 231
  2. 506
  3. 880
  4. 825
  5. 759
  6. 682
  7. 781
  8. 363
  9. 649
  10. 671
  11. 484
  12. 473
  13. 693
  14. 484
  15. 583
  16. 858
  17. 550
  18. 671
  19. 759
  20. 803
  21. 880
  22. 517
  23. 957
  24. 1012
  25. 473
  26. 1034
  27. 286
  28. 308
  29. 418
  30. 957
  31. 1023
  32. 143
  33. 847
  34. 517
  35. 726
  36. 528
  37. 1056
  38. 1232
  39. 572
  40. 759

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