← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 668 · 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 + 2 + 11 + 13 + 24 + 37 + 61 + 98 + 159 + 257 =
  2. 2.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?
  3. 3.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?
  4. 4.2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 =
  5. 5.Leapfrog list (each number is the sum of the two before it): 7, 4, 11, 15, 26, 41, 67, 108, 175, 283. What is 11 × the 7th number?
  6. 6.Leapfrog list (each number is the sum of the two before it): 1, 8, 9, 17, 26, 43, 69, 112, 181, 293. What is 11 × the 7th number?
  7. 7.3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 + 233 =
  8. 8.9 + 1 + 10 + 11 + 21 + 32 + 53 + 85 + 138 + 223 =
  9. 9.A leapfrog list starts 1, 2 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 2, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  11. 11.8 + 7 + 15 + 22 + 37 + 59 + 96 + 155 + 251 + 406 =
  12. 12.4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 + 322 =
  13. 13.9 + 3 + 12 + 15 + 27 + 42 + 69 + 111 + 180 + 291 =
  14. 14.1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 =
  15. 15.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?
  16. 16.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?
  17. 17.A leapfrog list starts 6, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  18. 18.2 + 9 + 11 + 20 + 31 + 51 + 82 + 133 + 215 + 348 =
  19. 19.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?
  20. 20.3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 =
  21. 21.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?
  22. 22.6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 + 432 =
  23. 23.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?
  24. 24.3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 + 335 =
  25. 25.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?
  26. 26.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?
  27. 27.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?
  28. 28.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?
  29. 29.3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 + 369 =
  30. 30.Leapfrog list (each number is the sum of the two before it): 6, 9, 15, 24, 39, 63, 102, 165, 267, 432. What is 11 × the 7th number?
  31. 31.3 + 2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 =
  32. 32.9 + 5 + 14 + 19 + 33 + 52 + 85 + 137 + 222 + 359 =
  33. 33.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?
  34. 34.Leapfrog list (each number is the sum of the two before it): 1, 3, 4, 7, 11, 18, 29, 47, 76, 123. What is 11 × the 7th number?
  35. 35.4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 + 178 + 288 =
  36. 36.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?
  37. 37.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?
  38. 38.A leapfrog list starts 1, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  39. 39.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?
  40. 40.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?

Answer key

  1. 671
  2. 561
  3. 814
  4. 550
  5. 737
  6. 759
  7. 605
  8. 583
  9. 231
  10. 726
  11. 1056
  12. 836
  13. 759
  14. 407
  15. 704
  16. 902
  17. 682
  18. 902
  19. 308
  20. 517
  21. 341
  22. 1122
  23. 341
  24. 869
  25. 495
  26. 462
  27. 374
  28. 539
  29. 957
  30. 1122
  31. 341
  32. 935
  33. 847
  34. 319
  35. 748
  36. 1287
  37. 308
  38. 671
  39. 737
  40. 814

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