← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 172 · 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): 8, 8, 16, 24, 40, 64, 104, 168, 272, 440. What is 11 × the 7th number?
  2. 2.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?
  3. 3.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?
  4. 4.8 + 4 + 12 + 16 + 28 + 44 + 72 + 116 + 188 + 304 =
  5. 5.4 + 2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 =
  6. 6.A leapfrog list starts 2, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  7. 7.6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 + 225 + 364 =
  8. 8.5 + 5 + 10 + 15 + 25 + 40 + 65 + 105 + 170 + 275 =
  9. 9.5 + 2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 =
  10. 10.A leapfrog list starts 7, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  11. 11.7 + 4 + 11 + 15 + 26 + 41 + 67 + 108 + 175 + 283 =
  12. 12.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?
  13. 13.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?
  14. 14.Leapfrog list (each number is the sum of the two before it): 4, 6, 10, 16, 26, 42, 68, 110, 178, 288. What is 11 × the 7th number?
  15. 15.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?
  16. 16.A leapfrog list starts 2, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  17. 17.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?
  18. 18.9 + 7 + 16 + 23 + 39 + 62 + 101 + 163 + 264 + 427 =
  19. 19.4 + 8 + 12 + 20 + 32 + 52 + 84 + 136 + 220 + 356 =
  20. 20.6 + 1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 =
  21. 21.Leapfrog list (each number is the sum of the two before it): 8, 7, 15, 22, 37, 59, 96, 155, 251, 406. What is 11 × the 7th number?
  22. 22.2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 =
  23. 23.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?
  24. 24.9 + 6 + 15 + 21 + 36 + 57 + 93 + 150 + 243 + 393 =
  25. 25.4 + 1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 =
  26. 26.A leapfrog list starts 9, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  27. 27.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?
  28. 28.Leapfrog list (each number is the sum of the two before it): 3, 6, 9, 15, 24, 39, 63, 102, 165, 267. What is 11 × the 7th number?
  29. 29.7 + 1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 =
  30. 30.5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 + 343 =
  31. 31.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?
  32. 32.A leapfrog list starts 8, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  33. 33.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?
  34. 34.2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 + 280 =
  35. 35.8 + 6 + 14 + 20 + 34 + 54 + 88 + 142 + 230 + 372 =
  36. 36.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?
  37. 37.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?
  38. 38.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?
  39. 39.6 + 3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 =
  40. 40.5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 + 191 + 309 =

Answer key

  1. 1144
  2. 231
  3. 561
  4. 792
  5. 396
  6. 550
  7. 946
  8. 715
  9. 451
  10. 913
  11. 737
  12. 1023
  13. 418
  14. 748
  15. 1034
  16. 198
  17. 429
  18. 1111
  19. 924
  20. 418
  21. 1056
  22. 550
  23. 594
  24. 1023
  25. 308
  26. 935
  27. 143
  28. 693
  29. 473
  30. 891
  31. 781
  32. 1144
  33. 341
  34. 726
  35. 968
  36. 726
  37. 858
  38. 847
  39. 594
  40. 803

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