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
- 1.3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 + 335 =
- 2.A leapfrog list starts 1, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 3.Leapfrog list (each number is the sum of the two before it): 8, 5, 13, 18, 31, 49, 80, 129, 209, 338. What is 11 × the 7th number?
- 4.9 + 3 + 12 + 15 + 27 + 42 + 69 + 111 + 180 + 291 =
- 5.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?
- 6.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?
- 7.A leapfrog list starts 1, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 8.A leapfrog list starts 1, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 9.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?
- 10.1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 + 225 =
- 11.Leapfrog list (each number is the sum of the two before it): 2, 5, 7, 12, 19, 31, 50, 81, 131, 212. What is 11 × the 7th number?
- 12.A leapfrog list starts 4, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 13.Leapfrog list (each number is the sum of the two before it): 1, 7, 8, 15, 23, 38, 61, 99, 160, 259. What is 11 × the 7th number?
- 14.2 + 4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 + 178 =
- 15.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?
- 16.6 + 3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 =
- 17.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?
- 18.8 + 5 + 13 + 18 + 31 + 49 + 80 + 129 + 209 + 338 =
- 19.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?
- 20.7 + 5 + 12 + 17 + 29 + 46 + 75 + 121 + 196 + 317 =
- 21.A leapfrog list starts 8, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 22.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?
- 23.Leapfrog list (each number is the sum of the two before it): 8, 8, 16, 24, 40, 64, 104, 168, 272, 440. What is 11 × the 7th number?
- 24.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?
- 25.Leapfrog list (each number is the sum of the two before it): 7, 7, 14, 21, 35, 56, 91, 147, 238, 385. What is 11 × the 7th number?
- 26.4 + 9 + 13 + 22 + 35 + 57 + 92 + 149 + 241 + 390 =
- 27.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?
- 28.4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 + 178 + 288 =
- 29.6 + 2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 =
- 30.A leapfrog list starts 5, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 31.3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 + 369 =
- 32.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?
- 33.Leapfrog list (each number is the sum of the two before it): 9, 8, 17, 25, 42, 67, 109, 176, 285, 461. What is 11 × the 7th number?
- 34.5 + 1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 =
- 35.A leapfrog list starts 4, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 36.A leapfrog list starts 6, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 37.Leapfrog list (each number is the sum of the two before it): 3, 9, 12, 21, 33, 54, 87, 141, 228, 369. What is 11 × the 7th number?
- 38.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?
- 39.6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 + 246 + 398 =
- 40.6 + 5 + 11 + 16 + 27 + 43 + 70 + 113 + 183 + 296 =
Answer key
- 869
- 231
- 880
- 759
- 1001
- 605
- 671
- 759
- 451
- 583
- 550
- 484
- 671
- 462
- 902
- 594
- 671
- 880
- 682
- 825
- 704
- 528
- 1144
- 253
- 1001
- 1012
- 814
- 748
- 506
- 891
- 957
- 1012
- 1199
- 363
- 748
- 506
- 957
- 418
- 1034
- 770
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks