← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 247 · 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 1, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  2. 2.9 + 2 + 11 + 13 + 24 + 37 + 61 + 98 + 159 + 257 =
  3. 3.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?
  4. 4.A leapfrog list starts 8, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  5. 5.5 + 3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 =
  6. 6.A leapfrog list starts 6, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  7. 7.2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 + 246 =
  8. 8.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?
  9. 9.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?
  10. 10.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?
  11. 11.A leapfrog list starts 7, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  12. 12.Leapfrog list (each number is the sum of the two before it): 4, 3, 7, 10, 17, 27, 44, 71, 115, 186. What is 11 × the 7th number?
  13. 13.A leapfrog list starts 8, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  14. 14.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?
  15. 15.2 + 2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 =
  16. 16.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?
  17. 17.1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 =
  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): 6, 4, 10, 14, 24, 38, 62, 100, 162, 262. What is 11 × the 7th number?
  20. 20.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?
  21. 21.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?
  22. 22.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?
  23. 23.4 + 4 + 8 + 12 + 20 + 32 + 52 + 84 + 136 + 220 =
  24. 24.A leapfrog list starts 8, 7 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): 3, 4, 7, 11, 18, 29, 47, 76, 123, 199. What is 11 × the 7th number?
  26. 26.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?
  27. 27.1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 =
  28. 28.Leapfrog list (each number is the sum of the two before it): 8, 6, 14, 20, 34, 54, 88, 142, 230, 372. What is 11 × the 7th number?
  29. 29.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?
  30. 30.7 + 3 + 10 + 13 + 23 + 36 + 59 + 95 + 154 + 249 =
  31. 31.6 + 1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 =
  32. 32.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?
  33. 33.3 + 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 =
  34. 34.Leapfrog list (each number is the sum of the two before it): 4, 7, 11, 18, 29, 47, 76, 123, 199, 322. What is 11 × the 7th number?
  35. 35.A leapfrog list starts 7, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  36. 36.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?
  37. 37.Leapfrog list (each number is the sum of the two before it): 4, 9, 13, 22, 35, 57, 92, 149, 241, 390. What is 11 × the 7th number?
  38. 38.A leapfrog list starts 8, 9 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 6, 8 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): 4, 1, 5, 6, 11, 17, 28, 45, 73, 118. What is 11 × the 7th number?

Answer key

  1. 759
  2. 671
  3. 858
  4. 968
  5. 539
  6. 946
  7. 638
  8. 539
  9. 671
  10. 649
  11. 825
  12. 484
  13. 880
  14. 1034
  15. 286
  16. 759
  17. 319
  18. 902
  19. 682
  20. 396
  21. 726
  22. 418
  23. 572
  24. 1056
  25. 517
  26. 671
  27. 231
  28. 968
  29. 902
  30. 649
  31. 418
  32. 550
  33. 253
  34. 836
  35. 473
  36. 913
  37. 1012
  38. 1232
  39. 1034
  40. 308

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