← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 652 · 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. 1.7 + 4 + 11 + 15 + 26 + 41 + 67 + 108 + 175 + 283 =
  2. 2.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?
  3. 3.A leapfrog list starts 7, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  4. 4.5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 + 343 =
  5. 5.7 + 7 + 14 + 21 + 35 + 56 + 91 + 147 + 238 + 385 =
  6. 6.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?
  7. 7.2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 + 280 =
  8. 8.1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 + 259 =
  9. 9.4 + 2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 =
  10. 10.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?
  11. 11.8 + 7 + 15 + 22 + 37 + 59 + 96 + 155 + 251 + 406 =
  12. 12.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?
  13. 13.4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 + 322 =
  14. 14.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
  15. 15.A leapfrog list starts 3, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  16. 16.9 + 3 + 12 + 15 + 27 + 42 + 69 + 111 + 180 + 291 =
  17. 17.8 + 2 + 10 + 12 + 22 + 34 + 56 + 90 + 146 + 236 =
  18. 18.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?
  19. 19.A leapfrog list starts 6, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  20. 20.Leapfrog list (each number is the sum of the two before it): 6, 7, 13, 20, 33, 53, 86, 139, 225, 364. What is 11 × the 7th number?
  21. 21.Leapfrog list (each number is the sum of the two before it): 8, 4, 12, 16, 28, 44, 72, 116, 188, 304. What is 11 × the 7th number?
  22. 22.Leapfrog list (each number is the sum of the two before it): 7, 5, 12, 17, 29, 46, 75, 121, 196, 317. What is 11 × the 7th number?
  23. 23.2 + 2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 =
  24. 24.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?
  25. 25.A leapfrog list starts 5, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  26. 26.3 + 2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 =
  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. 28.8 + 4 + 12 + 16 + 28 + 44 + 72 + 116 + 188 + 304 =
  29. 29.9 + 6 + 15 + 21 + 36 + 57 + 93 + 150 + 243 + 393 =
  30. 30.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?
  31. 31.Leapfrog list (each number is the sum of the two before it): 8, 5, 13, 18, 31, 49, 80, 129, 209, 338. What is 11 × the 7th number?
  32. 32.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?
  33. 33.Leapfrog list (each number is the sum of the two before it): 1, 2, 3, 5, 8, 13, 21, 34, 55, 89. What is 11 × the 7th number?
  34. 34.2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 + 314 =
  35. 35.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?
  36. 36.Leapfrog list (each number is the sum of the two before it): 7, 7, 14, 21, 35, 56, 91, 147, 238, 385. What is 11 × the 7th number?
  37. 37.Leapfrog list (each number is the sum of the two before it): 5, 9, 14, 23, 37, 60, 97, 157, 254, 411. What is 11 × the 7th number?
  38. 38.7 + 6 + 13 + 19 + 32 + 51 + 83 + 134 + 217 + 351 =
  39. 39.3 + 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 =
  40. 40.4 + 4 + 8 + 12 + 20 + 32 + 52 + 84 + 136 + 220 =

Answer key

  1. 737
  2. 902
  3. 649
  4. 891
  5. 1001
  6. 407
  7. 726
  8. 671
  9. 396
  10. 407
  11. 1056
  12. 660
  13. 836
  14. 781
  15. 693
  16. 759
  17. 616
  18. 1012
  19. 770
  20. 946
  21. 792
  22. 825
  23. 286
  24. 594
  25. 979
  26. 341
  27. 638
  28. 792
  29. 1023
  30. 913
  31. 880
  32. 583
  33. 231
  34. 814
  35. 539
  36. 1001
  37. 1067
  38. 913
  39. 253
  40. 572

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