← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 308 · 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 5, 1 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 9, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  3. 3.3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 + 369 =
  4. 4.6 + 3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 =
  5. 5.A leapfrog list starts 7, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  6. 6.Leapfrog list (each number is the sum of the two before it): 9, 7, 16, 23, 39, 62, 101, 163, 264, 427. What is 11 × the 7th number?
  7. 7.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?
  8. 8.A leapfrog list starts 6, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  9. 9.3 + 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 =
  10. 10.5 + 3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 =
  11. 11.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?
  12. 12.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?
  13. 13.2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 + 314 =
  14. 14.A leapfrog list starts 8, 6 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 3, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  16. 16.5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 + 254 + 411 =
  17. 17.Leapfrog list (each number is the sum of the two before it): 5, 8, 13, 21, 34, 55, 89, 144, 233, 377. What is 11 × the 7th number?
  18. 18.6 + 4 + 10 + 14 + 24 + 38 + 62 + 100 + 162 + 262 =
  19. 19.Leapfrog list (each number is the sum of the two before it): 2, 4, 6, 10, 16, 26, 42, 68, 110, 178. What is 11 × the 7th number?
  20. 20.9 + 5 + 14 + 19 + 33 + 52 + 85 + 137 + 222 + 359 =
  21. 21.A leapfrog list starts 7, 9 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): 6, 6, 12, 18, 30, 48, 78, 126, 204, 330. What is 11 × the 7th number?
  23. 23.2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 =
  24. 24.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?
  25. 25.A leapfrog list starts 3, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  26. 26.3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 + 233 =
  27. 27.3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 + 335 =
  28. 28.Leapfrog list (each number is the sum of the two before it): 2, 7, 9, 16, 25, 41, 66, 107, 173, 280. What is 11 × the 7th number?
  29. 29.6 + 6 + 12 + 18 + 30 + 48 + 78 + 126 + 204 + 330 =
  30. 30.Leapfrog list (each number is the sum of the two before it): 8, 7, 15, 22, 37, 59, 96, 155, 251, 406. What is 11 × the 7th number?
  31. 31.A leapfrog list starts 8, 9 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): 1, 4, 5, 9, 14, 23, 37, 60, 97, 157. What is 11 × the 7th number?
  33. 33.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?
  34. 34.8 + 3 + 11 + 14 + 25 + 39 + 64 + 103 + 167 + 270 =
  35. 35.9 + 4 + 13 + 17 + 30 + 47 + 77 + 124 + 201 + 325 =
  36. 36.1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 =
  37. 37.Leapfrog list (each number is the sum of the two before it): 8, 2, 10, 12, 22, 34, 56, 90, 146, 236. What is 11 × the 7th number?
  38. 38.Leapfrog list (each number is the sum of the two before it): 7, 1, 8, 9, 17, 26, 43, 69, 112, 181. What is 11 × the 7th number?
  39. 39.7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 + 259 + 419 =
  40. 40.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?

Answer key

  1. 363
  2. 1023
  3. 957
  4. 594
  5. 913
  6. 1111
  7. 660
  8. 594
  9. 253
  10. 539
  11. 671
  12. 374
  13. 814
  14. 968
  15. 517
  16. 1067
  17. 979
  18. 682
  19. 462
  20. 935
  21. 1177
  22. 858
  23. 550
  24. 891
  25. 341
  26. 605
  27. 869
  28. 726
  29. 858
  30. 1056
  31. 1232
  32. 407
  33. 847
  34. 704
  35. 847
  36. 319
  37. 616
  38. 473
  39. 1089
  40. 638

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