Leapfrog Sum Trick Worksheet
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
- 1.2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 =
- 2.1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 + 225 =
- 3.1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 =
- 4.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?
- 5.A leapfrog list starts 2, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 6.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?
- 7.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?
- 8.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?
- 9.Leapfrog list (each number is the sum of the two before it): 7, 2, 9, 11, 20, 31, 51, 82, 133, 215. What is 11 × the 7th number?
- 10.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?
- 11.Leapfrog list (each number is the sum of the two before it): 7, 9, 16, 25, 41, 66, 107, 173, 280, 453. What is 11 × the 7th number?
- 12.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?
- 13.6 + 2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 =
- 14.Leapfrog list (each number is the sum of the two before it): 9, 4, 13, 17, 30, 47, 77, 124, 201, 325. What is 11 × the 7th number?
- 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?
- 16.2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 =
- 17.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?
- 18.Leapfrog list (each number is the sum of the two before it): 7, 6, 13, 19, 32, 51, 83, 134, 217, 351. What is 11 × the 7th number?
- 19.1 + 1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 =
- 20.5 + 1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 =
- 21.Leapfrog list (each number is the sum of the two before it): 2, 8, 10, 18, 28, 46, 74, 120, 194, 314. What is 11 × the 7th number?
- 22.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
- 23.A leapfrog list starts 2, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 24.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?
- 25.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?
- 26.8 + 8 + 16 + 24 + 40 + 64 + 104 + 168 + 272 + 440 =
- 27.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?
- 28.4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 + 254 =
- 29.1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 =
- 30.Leapfrog list (each number is the sum of the two before it): 2, 6, 8, 14, 22, 36, 58, 94, 152, 246. What is 11 × the 7th number?
- 31.6 + 1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 =
- 32.3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 =
- 33.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?
- 34.A leapfrog list starts 2, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 35.3 + 2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 =
- 36.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?
- 37.4 + 2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 =
- 38.Leapfrog list (each number is the sum of the two before it): 8, 1, 9, 10, 19, 29, 48, 77, 125, 202. What is 11 × the 7th number?
- 39.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?
- 40.2 + 2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 =
Answer key
- 374
- 583
- 759
- 616
- 198
- 803
- 418
- 462
- 561
- 308
- 1177
- 1001
- 506
- 847
- 770
- 550
- 143
- 913
- 143
- 363
- 814
- 781
- 726
- 473
- 660
- 1144
- 517
- 660
- 319
- 638
- 418
- 517
- 1199
- 374
- 341
- 594
- 396
- 528
- 594
- 286
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks