← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 817 · 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. 1.9 + 6 + 15 + 21 + 36 + 57 + 93 + 150 + 243 + 393 =
  2. 2.5 + 1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 =
  3. 3.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?
  4. 4.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?
  5. 5.Leapfrog list (each number is the sum of the two before it): 2, 4, 6, 10, 16, 26, 42, 68, 110, 178. What is 11 × the 7th number?
  6. 6.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?
  7. 7.Leapfrog list (each number is the sum of the two before it): 6, 2, 8, 10, 18, 28, 46, 74, 120, 194. What is 11 × the 7th number?
  8. 8.A leapfrog list starts 4, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  9. 9.A leapfrog list starts 1, 6 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): 6, 6, 12, 18, 30, 48, 78, 126, 204, 330. What is 11 × the 7th number?
  11. 11.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?
  12. 12.A leapfrog list starts 7, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  13. 13.8 + 2 + 10 + 12 + 22 + 34 + 56 + 90 + 146 + 236 =
  14. 14.2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 =
  15. 15.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?
  16. 16.A leapfrog list starts 7, 9 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): 7, 3, 10, 13, 23, 36, 59, 95, 154, 249. What is 11 × the 7th number?
  18. 18.A leapfrog list starts 9, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  19. 19.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?
  20. 20.A leapfrog list starts 5, 5 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): 2, 9, 11, 20, 31, 51, 82, 133, 215, 348. What is 11 × the 7th number?
  22. 22.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?
  23. 23.Leapfrog list (each number is the sum of the two before it): 2, 2, 4, 6, 10, 16, 26, 42, 68, 110. What is 11 × the 7th number?
  24. 24.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?
  25. 25.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?
  26. 26.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?
  27. 27.8 + 3 + 11 + 14 + 25 + 39 + 64 + 103 + 167 + 270 =
  28. 28.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?
  29. 29.A leapfrog list starts 1, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  30. 30.6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 + 432 =
  31. 31.1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 + 191 =
  32. 32.2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 + 314 =
  33. 33.4 + 1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 =
  34. 34.1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 =
  35. 35.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?
  36. 36.5 + 4 + 9 + 13 + 22 + 35 + 57 + 92 + 149 + 241 =
  37. 37.7 + 6 + 13 + 19 + 32 + 51 + 83 + 134 + 217 + 351 =
  38. 38.7 + 7 + 14 + 21 + 35 + 56 + 91 + 147 + 238 + 385 =
  39. 39.7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 + 280 + 453 =
  40. 40.1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 + 259 =

Answer key

  1. 1023
  2. 363
  3. 363
  4. 759
  5. 462
  6. 319
  7. 506
  8. 660
  9. 583
  10. 858
  11. 748
  12. 1089
  13. 616
  14. 374
  15. 1023
  16. 1177
  17. 649
  18. 583
  19. 253
  20. 715
  21. 902
  22. 451
  23. 286
  24. 517
  25. 880
  26. 539
  27. 704
  28. 1001
  29. 407
  30. 1122
  31. 495
  32. 814
  33. 308
  34. 231
  35. 539
  36. 627
  37. 913
  38. 1001
  39. 1177
  40. 671

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