← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 41 · 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 2, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  2. 2.3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 + 335 =
  3. 3.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?
  4. 4.6 + 5 + 11 + 16 + 27 + 43 + 70 + 113 + 183 + 296 =
  5. 5.9 + 7 + 16 + 23 + 39 + 62 + 101 + 163 + 264 + 427 =
  6. 6.Leapfrog list (each number is the sum of the two before it): 2, 8, 10, 18, 28, 46, 74, 120, 194, 314. What is 11 × the 7th number?
  7. 7.A leapfrog list starts 5, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  8. 8.4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 + 322 =
  9. 9.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?
  10. 10.Leapfrog list (each number is the sum of the two before it): 4, 2, 6, 8, 14, 22, 36, 58, 94, 152. What is 11 × the 7th number?
  11. 11.7 + 6 + 13 + 19 + 32 + 51 + 83 + 134 + 217 + 351 =
  12. 12.Leapfrog list (each number is the sum of the two before it): 7, 8, 15, 23, 38, 61, 99, 160, 259, 419. What is 11 × the 7th number?
  13. 13.2 + 2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 =
  14. 14.7 + 1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 =
  15. 15.7 + 3 + 10 + 13 + 23 + 36 + 59 + 95 + 154 + 249 =
  16. 16.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?
  17. 17.4 + 2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 =
  18. 18.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?
  19. 19.A leapfrog list starts 7, 4 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): 3, 3, 6, 9, 15, 24, 39, 63, 102, 165. What is 11 × the 7th number?
  21. 21.2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 + 178 =
  22. 22.3 + 2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 =
  23. 23.Leapfrog list (each number is the sum of the two before it): 1, 5, 6, 11, 17, 28, 45, 73, 118, 191. What is 11 × the 7th number?
  24. 24.A leapfrog list starts 6, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  25. 25.2 + 1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 =
  26. 26.5 + 3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 =
  27. 27.Leapfrog list (each number is the sum of the two before it): 3, 2, 5, 7, 12, 19, 31, 50, 81, 131. What is 11 × the 7th number?
  28. 28.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?
  29. 29.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?
  30. 30.9 + 2 + 11 + 13 + 24 + 37 + 61 + 98 + 159 + 257 =
  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.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?
  33. 33.3 + 3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 =
  34. 34.1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 =
  35. 35.6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 + 225 + 364 =
  36. 36.Leapfrog list (each number is the sum of the two before it): 2, 9, 11, 20, 31, 51, 82, 133, 215, 348. What is 11 × the 7th number?
  37. 37.A leapfrog list starts 2, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  38. 38.7 + 2 + 9 + 11 + 20 + 31 + 51 + 82 + 133 + 215 =
  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. 40.9 + 6 + 15 + 21 + 36 + 57 + 93 + 150 + 243 + 393 =

Answer key

  1. 374
  2. 869
  3. 759
  4. 770
  5. 1111
  6. 814
  7. 539
  8. 836
  9. 528
  10. 396
  11. 913
  12. 1089
  13. 286
  14. 473
  15. 649
  16. 616
  17. 396
  18. 858
  19. 737
  20. 429
  21. 462
  22. 341
  23. 495
  24. 1122
  25. 198
  26. 539
  27. 341
  28. 1177
  29. 748
  30. 671
  31. 869
  32. 770
  33. 429
  34. 231
  35. 946
  36. 902
  37. 726
  38. 561
  39. 561
  40. 1023

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