← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 437 · 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, 5, 14, 19, 33, 52, 85, 137, 222, 359. What is 11 × the 7th number?
  2. 2.6 + 1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 =
  3. 3.3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 =
  4. 4.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?
  5. 5.Leapfrog list (each number is the sum of the two before it): 1, 1, 2, 3, 5, 8, 13, 21, 34, 55. What is 11 × the 7th number?
  6. 6.A leapfrog list starts 3, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  7. 7.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?
  8. 8.A leapfrog list starts 8, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  9. 9.7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 + 259 + 419 =
  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.A leapfrog list starts 3, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  12. 12.2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 + 246 =
  13. 13.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?
  14. 14.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?
  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. 16.3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 + 233 =
  17. 17.A leapfrog list starts 3, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  18. 18.1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 =
  19. 19.A leapfrog list starts 4, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  20. 20.7 + 7 + 14 + 21 + 35 + 56 + 91 + 147 + 238 + 385 =
  21. 21.Leapfrog list (each number is the sum of the two before it): 6, 3, 9, 12, 21, 33, 54, 87, 141, 228. What is 11 × the 7th number?
  22. 22.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?
  23. 23.8 + 5 + 13 + 18 + 31 + 49 + 80 + 129 + 209 + 338 =
  24. 24.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?
  25. 25.2 + 2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 =
  26. 26.A leapfrog list starts 4, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  27. 27.A leapfrog list starts 9, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  28. 28.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?
  29. 29.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?
  30. 30.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?
  31. 31.A leapfrog list starts 8, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  32. 32.5 + 5 + 10 + 15 + 25 + 40 + 65 + 105 + 170 + 275 =
  33. 33.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?
  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. 35.6 + 2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 =
  36. 36.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?
  37. 37.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?
  38. 38.1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 =
  39. 39.Leapfrog list (each number is the sum of the two before it): 6, 5, 11, 16, 27, 43, 70, 113, 183, 296. What is 11 × the 7th number?
  40. 40.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?

Answer key

  1. 935
  2. 418
  3. 693
  4. 484
  5. 143
  6. 517
  7. 539
  8. 792
  9. 1089
  10. 407
  11. 605
  12. 638
  13. 682
  14. 231
  15. 627
  16. 605
  17. 869
  18. 231
  19. 1012
  20. 1001
  21. 594
  22. 726
  23. 880
  24. 605
  25. 286
  26. 396
  27. 1287
  28. 946
  29. 693
  30. 715
  31. 616
  32. 715
  33. 253
  34. 836
  35. 506
  36. 902
  37. 495
  38. 759
  39. 770
  40. 561

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