← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 277 · 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): 5, 2, 7, 9, 16, 25, 41, 66, 107, 173. What is 11 × the 7th number?
  2. 2.7 + 3 + 10 + 13 + 23 + 36 + 59 + 95 + 154 + 249 =
  3. 3.4 + 8 + 12 + 20 + 32 + 52 + 84 + 136 + 220 + 356 =
  4. 4.3 + 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 =
  5. 5.7 + 6 + 13 + 19 + 32 + 51 + 83 + 134 + 217 + 351 =
  6. 6.Leapfrog list (each number is the sum of the two before it): 4, 2, 6, 8, 14, 22, 36, 58, 94, 152. What is 11 × the 7th number?
  7. 7.6 + 2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 =
  8. 8.Leapfrog list (each number is the sum of the two before it): 1, 6, 7, 13, 20, 33, 53, 86, 139, 225. What is 11 × the 7th number?
  9. 9.4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 + 322 =
  10. 10.A leapfrog list starts 4, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  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.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?
  13. 13.4 + 9 + 13 + 22 + 35 + 57 + 92 + 149 + 241 + 390 =
  14. 14.5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 + 191 + 309 =
  15. 15.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?
  16. 16.A leapfrog list starts 5, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  17. 17.A leapfrog list starts 9, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  18. 18.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?
  19. 19.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?
  20. 20.Leapfrog list (each number is the sum of the two before it): 4, 5, 9, 14, 23, 37, 60, 97, 157, 254. What is 11 × the 7th number?
  21. 21.Leapfrog list (each number is the sum of the two before it): 4, 9, 13, 22, 35, 57, 92, 149, 241, 390. What is 11 × the 7th number?
  22. 22.7 + 1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 =
  23. 23.A leapfrog list starts 9, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  24. 24.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?
  25. 25.6 + 5 + 11 + 16 + 27 + 43 + 70 + 113 + 183 + 296 =
  26. 26.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
  27. 27.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?
  28. 28.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?
  29. 29.1 + 1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 =
  30. 30.6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 + 225 + 364 =
  31. 31.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?
  32. 32.2 + 9 + 11 + 20 + 31 + 51 + 82 + 133 + 215 + 348 =
  33. 33.9 + 1 + 10 + 11 + 21 + 32 + 53 + 85 + 138 + 223 =
  34. 34.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?
  35. 35.6 + 1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 =
  36. 36.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?
  37. 37.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?
  38. 38.5 + 5 + 10 + 15 + 25 + 40 + 65 + 105 + 170 + 275 =
  39. 39.Leapfrog list (each number is the sum of the two before it): 9, 2, 11, 13, 24, 37, 61, 98, 159, 257. What is 11 × the 7th number?
  40. 40.A leapfrog list starts 5, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?

Answer key

  1. 451
  2. 649
  3. 924
  4. 253
  5. 913
  6. 396
  7. 506
  8. 583
  9. 836
  10. 836
  11. 374
  12. 253
  13. 1012
  14. 803
  15. 935
  16. 627
  17. 1199
  18. 418
  19. 968
  20. 660
  21. 1012
  22. 473
  23. 847
  24. 418
  25. 770
  26. 781
  27. 924
  28. 583
  29. 143
  30. 946
  31. 759
  32. 902
  33. 583
  34. 1177
  35. 418
  36. 341
  37. 1144
  38. 715
  39. 671
  40. 715

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