← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 174 · 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. 1.3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 =
  2. 2.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?
  3. 3.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?
  4. 4.4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 + 254 =
  5. 5.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?
  6. 6.8 + 4 + 12 + 16 + 28 + 44 + 72 + 116 + 188 + 304 =
  7. 7.7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 + 259 + 419 =
  8. 8.7 + 1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 =
  9. 9.5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 + 343 =
  10. 10.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?
  11. 11.8 + 6 + 14 + 20 + 34 + 54 + 88 + 142 + 230 + 372 =
  12. 12.Leapfrog list (each number is the sum of the two before it): 5, 4, 9, 13, 22, 35, 57, 92, 149, 241. What is 11 × the 7th number?
  13. 13.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?
  14. 14.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?
  15. 15.Leapfrog list (each number is the sum of the two before it): 7, 8, 15, 23, 38, 61, 99, 160, 259, 419. What is 11 × the 7th number?
  16. 16.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?
  17. 17.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?
  18. 18.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?
  19. 19.3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 + 233 =
  20. 20.Leapfrog list (each number is the sum of the two before it): 3, 5, 8, 13, 21, 34, 55, 89, 144, 233. What is 11 × the 7th number?
  21. 21.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?
  22. 22.Leapfrog list (each number is the sum of the two before it): 9, 3, 12, 15, 27, 42, 69, 111, 180, 291. What is 11 × the 7th number?
  23. 23.9 + 9 + 18 + 27 + 45 + 72 + 117 + 189 + 306 + 495 =
  24. 24.Leapfrog list (each number is the sum of the two before it): 5, 7, 12, 19, 31, 50, 81, 131, 212, 343. What is 11 × the 7th number?
  25. 25.2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 =
  26. 26.A leapfrog list starts 4, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  27. 27.1 + 9 + 10 + 19 + 29 + 48 + 77 + 125 + 202 + 327 =
  28. 28.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?
  29. 29.4 + 1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 =
  30. 30.A leapfrog list starts 1, 1 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): 8, 6, 14, 20, 34, 54, 88, 142, 230, 372. What is 11 × the 7th number?
  32. 32.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?
  33. 33.2 + 2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 =
  34. 34.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?
  35. 35.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?
  36. 36.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?
  37. 37.7 + 3 + 10 + 13 + 23 + 36 + 59 + 95 + 154 + 249 =
  38. 38.5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 + 254 + 411 =
  39. 39.4 + 3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 =
  40. 40.Leapfrog list (each number is the sum of the two before it): 3, 6, 9, 15, 24, 39, 63, 102, 165, 267. What is 11 × the 7th number?

Answer key

  1. 517
  2. 286
  3. 1001
  4. 660
  5. 550
  6. 792
  7. 1089
  8. 473
  9. 891
  10. 638
  11. 968
  12. 627
  13. 583
  14. 341
  15. 1089
  16. 1111
  17. 1056
  18. 231
  19. 605
  20. 605
  21. 539
  22. 759
  23. 1287
  24. 891
  25. 550
  26. 484
  27. 847
  28. 1122
  29. 308
  30. 143
  31. 968
  32. 1056
  33. 286
  34. 594
  35. 407
  36. 737
  37. 649
  38. 1067
  39. 484
  40. 693

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