← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 442 · 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): 9, 7, 16, 23, 39, 62, 101, 163, 264, 427. What is 11 × the 7th number?
  2. 2.Leapfrog list (each number is the sum of the two before it): 1, 4, 5, 9, 14, 23, 37, 60, 97, 157. What is 11 × the 7th number?
  3. 3.Leapfrog list (each number is the sum of the two before it): 8, 7, 15, 22, 37, 59, 96, 155, 251, 406. What is 11 × the 7th number?
  4. 4.A leapfrog list starts 5, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  5. 5.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?
  6. 6.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?
  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.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?
  9. 9.7 + 6 + 13 + 19 + 32 + 51 + 83 + 134 + 217 + 351 =
  10. 10.3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 + 233 =
  11. 11.8 + 2 + 10 + 12 + 22 + 34 + 56 + 90 + 146 + 236 =
  12. 12.1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 =
  13. 13.6 + 1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 =
  14. 14.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?
  15. 15.5 + 1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 =
  16. 16.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?
  17. 17.A leapfrog list starts 2, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  18. 18.8 + 4 + 12 + 16 + 28 + 44 + 72 + 116 + 188 + 304 =
  19. 19.3 + 3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 =
  20. 20.6 + 3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 =
  21. 21.Leapfrog list (each number is the sum of the two before it): 2, 7, 9, 16, 25, 41, 66, 107, 173, 280. What is 11 × the 7th number?
  22. 22.A leapfrog list starts 4, 6 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): 4, 3, 7, 10, 17, 27, 44, 71, 115, 186. What is 11 × the 7th number?
  24. 24.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?
  25. 25.2 + 2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 =
  26. 26.3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 =
  27. 27.Leapfrog list (each number is the sum of the two before it): 2, 6, 8, 14, 22, 36, 58, 94, 152, 246. What is 11 × the 7th number?
  28. 28.A leapfrog list starts 3, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  29. 29.4 + 2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 =
  30. 30.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?
  31. 31.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?
  32. 32.A leapfrog list starts 6, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  33. 33.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?
  34. 34.5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 + 254 + 411 =
  35. 35.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
  36. 36.1 + 1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 =
  37. 37.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?
  38. 38.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?
  39. 39.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?
  40. 40.Leapfrog list (each number is the sum of the two before it): 2, 1, 3, 4, 7, 11, 18, 29, 47, 76. What is 11 × the 7th number?

Answer key

  1. 1111
  2. 407
  3. 1056
  4. 1067
  5. 1122
  6. 671
  7. 1177
  8. 561
  9. 913
  10. 605
  11. 616
  12. 759
  13. 418
  14. 682
  15. 363
  16. 429
  17. 462
  18. 792
  19. 429
  20. 594
  21. 726
  22. 748
  23. 484
  24. 649
  25. 286
  26. 517
  27. 638
  28. 781
  29. 396
  30. 1056
  31. 495
  32. 506
  33. 1023
  34. 1067
  35. 781
  36. 143
  37. 374
  38. 946
  39. 913
  40. 198

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