← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 471 · 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. 1.1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 =
  2. 2.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?
  3. 3.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?
  4. 4.Leapfrog list (each number is the sum of the two before it): 1, 3, 4, 7, 11, 18, 29, 47, 76, 123. What is 11 × the 7th number?
  5. 5.4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 + 178 + 288 =
  6. 6.1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 + 191 =
  7. 7.9 + 8 + 17 + 25 + 42 + 67 + 109 + 176 + 285 + 461 =
  8. 8.4 + 3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 =
  9. 9.5 + 5 + 10 + 15 + 25 + 40 + 65 + 105 + 170 + 275 =
  10. 10.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?
  11. 11.Leapfrog list (each number is the sum of the two before it): 2, 3, 5, 8, 13, 21, 34, 55, 89, 144. What is 11 × the 7th number?
  12. 12.1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 + 225 =
  13. 13.4 + 2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 =
  14. 14.A leapfrog list starts 8, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  15. 15.3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 + 369 =
  16. 16.4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 + 322 =
  17. 17.A leapfrog list starts 7, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  18. 18.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?
  19. 19.4 + 8 + 12 + 20 + 32 + 52 + 84 + 136 + 220 + 356 =
  20. 20.7 + 1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 =
  21. 21.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?
  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. 23.6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 + 225 + 364 =
  24. 24.A leapfrog list starts 7, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  25. 25.7 + 6 + 13 + 19 + 32 + 51 + 83 + 134 + 217 + 351 =
  26. 26.7 + 3 + 10 + 13 + 23 + 36 + 59 + 95 + 154 + 249 =
  27. 27.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?
  28. 28.7 + 5 + 12 + 17 + 29 + 46 + 75 + 121 + 196 + 317 =
  29. 29.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?
  30. 30.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?
  31. 31.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?
  32. 32.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?
  33. 33.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?
  34. 34.A leapfrog list starts 9, 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 6, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  36. 36.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?
  37. 37.7 + 2 + 9 + 11 + 20 + 31 + 51 + 82 + 133 + 215 =
  38. 38.A leapfrog list starts 3, 1 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): 8, 4, 12, 16, 28, 44, 72, 116, 188, 304. What is 11 × the 7th number?
  40. 40.A leapfrog list starts 9, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?

Answer key

  1. 407
  2. 671
  3. 1111
  4. 319
  5. 748
  6. 495
  7. 1199
  8. 484
  9. 715
  10. 143
  11. 374
  12. 583
  13. 396
  14. 1144
  15. 957
  16. 836
  17. 825
  18. 924
  19. 924
  20. 473
  21. 319
  22. 825
  23. 946
  24. 1001
  25. 913
  26. 649
  27. 869
  28. 825
  29. 924
  30. 836
  31. 517
  32. 968
  33. 682
  34. 759
  35. 1122
  36. 253
  37. 561
  38. 253
  39. 792
  40. 583

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