← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 80 · 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 4, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  2. 2.2 + 1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 =
  3. 3.4 + 2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 =
  4. 4.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?
  5. 5.3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 + 233 =
  6. 6.8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 + 474 =
  7. 7.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?
  8. 8.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?
  9. 9.6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 + 432 =
  10. 10.5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 + 343 =
  11. 11.A leapfrog list starts 2, 9 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 3, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  13. 13.2 + 2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 =
  14. 14.A leapfrog list starts 6, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  15. 15.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?
  16. 16.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?
  17. 17.3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 =
  18. 18.8 + 8 + 16 + 24 + 40 + 64 + 104 + 168 + 272 + 440 =
  19. 19.8 + 2 + 10 + 12 + 22 + 34 + 56 + 90 + 146 + 236 =
  20. 20.9 + 9 + 18 + 27 + 45 + 72 + 117 + 189 + 306 + 495 =
  21. 21.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?
  22. 22.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?
  23. 23.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?
  24. 24.9 + 5 + 14 + 19 + 33 + 52 + 85 + 137 + 222 + 359 =
  25. 25.7 + 2 + 9 + 11 + 20 + 31 + 51 + 82 + 133 + 215 =
  26. 26.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?
  27. 27.Leapfrog list (each number is the sum of the two before it): 4, 3, 7, 10, 17, 27, 44, 71, 115, 186. What is 11 × the 7th number?
  28. 28.8 + 3 + 11 + 14 + 25 + 39 + 64 + 103 + 167 + 270 =
  29. 29.5 + 2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 =
  30. 30.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
  31. 31.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?
  32. 32.Leapfrog list (each number is the sum of the two before it): 3, 2, 5, 7, 12, 19, 31, 50, 81, 131. What is 11 × the 7th number?
  33. 33.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?
  34. 34.A leapfrog list starts 2, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  35. 35.4 + 1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 =
  36. 36.A leapfrog list starts 7, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  37. 37.2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 + 280 =
  38. 38.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?
  39. 39.4 + 9 + 13 + 22 + 35 + 57 + 92 + 149 + 241 + 390 =
  40. 40.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?

Answer key

  1. 748
  2. 198
  3. 396
  4. 737
  5. 605
  6. 1232
  7. 1067
  8. 803
  9. 1122
  10. 891
  11. 902
  12. 605
  13. 286
  14. 418
  15. 770
  16. 792
  17. 693
  18. 1144
  19. 616
  20. 1287
  21. 1287
  22. 484
  23. 594
  24. 935
  25. 561
  26. 572
  27. 484
  28. 704
  29. 451
  30. 781
  31. 946
  32. 341
  33. 968
  34. 638
  35. 308
  36. 1089
  37. 726
  38. 891
  39. 1012
  40. 759

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