← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 869 · 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, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  2. 2.A leapfrog list starts 1, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  3. 3.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?
  4. 4.7 + 1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 =
  5. 5.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?
  6. 6.Leapfrog list (each number is the sum of the two before it): 3, 1, 4, 5, 9, 14, 23, 37, 60, 97. What is 11 × the 7th number?
  7. 7.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?
  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. 9.7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 + 280 + 453 =
  10. 10.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?
  11. 11.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
  12. 12.9 + 5 + 14 + 19 + 33 + 52 + 85 + 137 + 222 + 359 =
  13. 13.A leapfrog list starts 4, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  14. 14.9 + 1 + 10 + 11 + 21 + 32 + 53 + 85 + 138 + 223 =
  15. 15.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?
  16. 16.6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 + 246 + 398 =
  17. 17.2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 + 314 =
  18. 18.A leapfrog list starts 4, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  19. 19.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?
  20. 20.A leapfrog list starts 4, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  21. 21.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?
  22. 22.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?
  23. 23.6 + 2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 =
  24. 24.Leapfrog list (each number is the sum of the two before it): 5, 5, 10, 15, 25, 40, 65, 105, 170, 275. What is 11 × the 7th number?
  25. 25.A leapfrog list starts 5, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  26. 26.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?
  27. 27.5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 + 343 =
  28. 28.7 + 2 + 9 + 11 + 20 + 31 + 51 + 82 + 133 + 215 =
  29. 29.Leapfrog list (each number is the sum of the two before it): 8, 1, 9, 10, 19, 29, 48, 77, 125, 202. What is 11 × the 7th number?
  30. 30.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?
  31. 31.1 + 9 + 10 + 19 + 29 + 48 + 77 + 125 + 202 + 327 =
  32. 32.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?
  33. 33.3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 + 233 =
  34. 34.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?
  35. 35.A leapfrog list starts 9, 6 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 4, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  37. 37.3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 + 335 =
  38. 38.9 + 8 + 17 + 25 + 42 + 67 + 109 + 176 + 285 + 461 =
  39. 39.A leapfrog list starts 1, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  40. 40.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?

Answer key

  1. 583
  2. 319
  3. 715
  4. 473
  5. 231
  6. 253
  7. 726
  8. 539
  9. 1177
  10. 946
  11. 781
  12. 935
  13. 308
  14. 583
  15. 627
  16. 1034
  17. 814
  18. 924
  19. 671
  20. 660
  21. 748
  22. 660
  23. 506
  24. 715
  25. 451
  26. 1067
  27. 891
  28. 561
  29. 528
  30. 682
  31. 847
  32. 495
  33. 605
  34. 429
  35. 1023
  36. 836
  37. 869
  38. 1199
  39. 847
  40. 682

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