← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 764 · 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): 4, 5, 9, 14, 23, 37, 60, 97, 157, 254. What is 11 × the 7th number?
  2. 2.Leapfrog list (each number is the sum of the two before it): 3, 7, 10, 17, 27, 44, 71, 115, 186, 301. What is 11 × the 7th number?
  3. 3.A leapfrog list starts 4, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  4. 4.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?
  5. 5.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?
  6. 6.A leapfrog list starts 3, 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): 7, 9, 16, 25, 41, 66, 107, 173, 280, 453. What is 11 × the 7th number?
  8. 8.2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 + 314 =
  9. 9.3 + 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 =
  10. 10.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?
  11. 11.A leapfrog list starts 9, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  12. 12.3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 + 335 =
  13. 13.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?
  14. 14.A leapfrog list starts 1, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  15. 15.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?
  16. 16.2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 + 280 =
  17. 17.7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 + 280 + 453 =
  18. 18.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?
  19. 19.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?
  20. 20.5 + 2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 =
  21. 21.5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 + 191 + 309 =
  22. 22.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?
  23. 23.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?
  24. 24.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?
  25. 25.5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 + 343 =
  26. 26.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?
  27. 27.A leapfrog list starts 4, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  28. 28.1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 =
  29. 29.1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 =
  30. 30.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?
  31. 31.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?
  32. 32.2 + 1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 =
  33. 33.3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 =
  34. 34.6 + 2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 =
  35. 35.Leapfrog list (each number is the sum of the two before it): 2, 3, 5, 8, 13, 21, 34, 55, 89, 144. What is 11 × the 7th number?
  36. 36.4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 + 254 =
  37. 37.4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 + 322 =
  38. 38.5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 + 254 + 411 =
  39. 39.Leapfrog list (each number is the sum of the two before it): 5, 6, 11, 17, 28, 45, 73, 118, 191, 309. What is 11 × the 7th number?
  40. 40.4 + 4 + 8 + 12 + 20 + 32 + 52 + 84 + 136 + 220 =

Answer key

  1. 660
  2. 781
  3. 396
  4. 902
  5. 407
  6. 429
  7. 1177
  8. 814
  9. 253
  10. 814
  11. 1111
  12. 869
  13. 429
  14. 495
  15. 363
  16. 726
  17. 1177
  18. 594
  19. 341
  20. 451
  21. 803
  22. 671
  23. 231
  24. 957
  25. 891
  26. 528
  27. 836
  28. 759
  29. 231
  30. 1001
  31. 715
  32. 198
  33. 517
  34. 506
  35. 374
  36. 660
  37. 836
  38. 1067
  39. 803
  40. 572

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