← The leapfrog sum trick lesson New set →

Leapfrog Sum Trick Worksheet

Maths tricks trick 25: The leapfrog sum trick · Set 397 · 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 9, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  2. 2.8 + 1 + 9 + 10 + 19 + 29 + 48 + 77 + 125 + 202 =
  3. 3.9 + 8 + 17 + 25 + 42 + 67 + 109 + 176 + 285 + 461 =
  4. 4.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?
  5. 5.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?
  6. 6.Leapfrog list (each number is the sum of the two before it): 6, 5, 11, 16, 27, 43, 70, 113, 183, 296. What is 11 × the 7th number?
  7. 7.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?
  8. 8.4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 + 254 =
  9. 9.9 + 2 + 11 + 13 + 24 + 37 + 61 + 98 + 159 + 257 =
  10. 10.A leapfrog list starts 1, 1 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): 5, 1, 6, 7, 13, 20, 33, 53, 86, 139. What is 11 × the 7th number?
  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.A leapfrog list starts 6, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  14. 14.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?
  15. 15.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?
  16. 16.9 + 4 + 13 + 17 + 30 + 47 + 77 + 124 + 201 + 325 =
  17. 17.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?
  18. 18.Leapfrog list (each number is the sum of the two before it): 2, 9, 11, 20, 31, 51, 82, 133, 215, 348. What is 11 × the 7th number?
  19. 19.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?
  20. 20.A leapfrog list starts 1, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  21. 21.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?
  22. 22.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?
  23. 23.7 + 7 + 14 + 21 + 35 + 56 + 91 + 147 + 238 + 385 =
  24. 24.7 + 4 + 11 + 15 + 26 + 41 + 67 + 108 + 175 + 283 =
  25. 25.9 + 3 + 12 + 15 + 27 + 42 + 69 + 111 + 180 + 291 =
  26. 26.Leapfrog list (each number is the sum of the two before it): 6, 4, 10, 14, 24, 38, 62, 100, 162, 262. What is 11 × the 7th number?
  27. 27.A leapfrog list starts 4, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  28. 28.Leapfrog list (each number is the sum of the two before it): 3, 6, 9, 15, 24, 39, 63, 102, 165, 267. What is 11 × the 7th number?
  29. 29.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?
  30. 30.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?
  31. 31.7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 + 259 + 419 =
  32. 32.A leapfrog list starts 8, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  33. 33.3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 + 233 =
  34. 34.A leapfrog list starts 8, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
  35. 35.8 + 3 + 11 + 14 + 25 + 39 + 64 + 103 + 167 + 270 =
  36. 36.2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 + 246 =
  37. 37.4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 + 178 + 288 =
  38. 38.4 + 1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 =
  39. 39.5 + 3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 =
  40. 40.6 + 1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 =

Answer key

  1. 1023
  2. 528
  3. 1199
  4. 1199
  5. 319
  6. 770
  7. 605
  8. 660
  9. 671
  10. 143
  11. 363
  12. 605
  13. 858
  14. 253
  15. 671
  16. 847
  17. 1001
  18. 902
  19. 341
  20. 583
  21. 792
  22. 935
  23. 1001
  24. 737
  25. 759
  26. 682
  27. 396
  28. 693
  29. 1023
  30. 308
  31. 1089
  32. 880
  33. 605
  34. 528
  35. 704
  36. 638
  37. 748
  38. 308
  39. 539
  40. 418

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