← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 933 · 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, 6, 15, 21, 36, 57, 93, 150, 243, 393. What is 11 × the 7th number?
  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 9, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  4. 4.9 + 1 + 10 + 11 + 21 + 32 + 53 + 85 + 138 + 223 =
  5. 5.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
  6. 6.8 + 6 + 14 + 20 + 34 + 54 + 88 + 142 + 230 + 372 =
  7. 7.Leapfrog list (each number is the sum of the two before it): 6, 1, 7, 8, 15, 23, 38, 61, 99, 160. What is 11 × the 7th number?
  8. 8.2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 =
  9. 9.9 + 3 + 12 + 15 + 27 + 42 + 69 + 111 + 180 + 291 =
  10. 10.3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 + 335 =
  11. 11.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?
  12. 12.A leapfrog list starts 2, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  13. 13.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?
  14. 14.A leapfrog list starts 8, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  15. 15.5 + 5 + 10 + 15 + 25 + 40 + 65 + 105 + 170 + 275 =
  16. 16.Leapfrog list (each number is the sum of the two before it): 1, 8, 9, 17, 26, 43, 69, 112, 181, 293. What is 11 × the 7th number?
  17. 17.Leapfrog list (each number is the sum of the two before it): 6, 2, 8, 10, 18, 28, 46, 74, 120, 194. What is 11 × the 7th number?
  18. 18.A leapfrog list starts 9, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  19. 19.A leapfrog list starts 9, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  20. 20.A leapfrog list starts 4, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  21. 21.1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 =
  22. 22.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?
  23. 23.Leapfrog list (each number is the sum of the two before it): 4, 8, 12, 20, 32, 52, 84, 136, 220, 356. What is 11 × the 7th number?
  24. 24.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?
  25. 25.3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 =
  26. 26.2 + 2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 =
  27. 27.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?
  28. 28.1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 + 191 =
  29. 29.A leapfrog list starts 5, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  30. 30.A leapfrog list starts 9, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  31. 31.1 + 1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 =
  32. 32.7 + 3 + 10 + 13 + 23 + 36 + 59 + 95 + 154 + 249 =
  33. 33.6 + 2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 =
  34. 34.Leapfrog list (each number is the sum of the two before it): 1, 9, 10, 19, 29, 48, 77, 125, 202, 327. What is 11 × the 7th number?
  35. 35.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?
  36. 36.Leapfrog list (each number is the sum of the two before it): 4, 6, 10, 16, 26, 42, 68, 110, 178, 288. What is 11 × the 7th number?
  37. 37.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?
  38. 38.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?
  39. 39.Leapfrog list (each number is the sum of the two before it): 9, 4, 13, 17, 30, 47, 77, 124, 201, 325. What is 11 × the 7th number?
  40. 40.Leapfrog list (each number is the sum of the two before it): 8, 9, 17, 26, 43, 69, 112, 181, 293, 474. What is 11 × the 7th number?

Answer key

  1. 1023
  2. 286
  3. 1023
  4. 583
  5. 781
  6. 968
  7. 418
  8. 374
  9. 759
  10. 869
  11. 792
  12. 814
  13. 605
  14. 704
  15. 715
  16. 759
  17. 506
  18. 671
  19. 935
  20. 572
  21. 759
  22. 649
  23. 924
  24. 319
  25. 517
  26. 286
  27. 308
  28. 495
  29. 803
  30. 1111
  31. 143
  32. 649
  33. 506
  34. 847
  35. 1177
  36. 748
  37. 484
  38. 660
  39. 847
  40. 1232

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