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
- 1.9 + 3 + 12 + 15 + 27 + 42 + 69 + 111 + 180 + 291 =
- 2.8 + 3 + 11 + 14 + 25 + 39 + 64 + 103 + 167 + 270 =
- 3.3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 =
- 4.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?
- 5.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?
- 6.A leapfrog list starts 6, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 7.3 + 3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 =
- 8.2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 =
- 9.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?
- 10.5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 + 233 + 377 =
- 11.A leapfrog list starts 9, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 12.1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 =
- 13.7 + 3 + 10 + 13 + 23 + 36 + 59 + 95 + 154 + 249 =
- 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.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?
- 16.5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 + 343 =
- 17.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?
- 18.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?
- 19.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?
- 20.Leapfrog list (each number is the sum of the two before it): 1, 5, 6, 11, 17, 28, 45, 73, 118, 191. What is 11 × the 7th number?
- 21.A leapfrog list starts 2, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 22.1 + 1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 =
- 23.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?
- 24.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?
- 25.Leapfrog list (each number is the sum of the two before it): 9, 3, 12, 15, 27, 42, 69, 111, 180, 291. What is 11 × the 7th number?
- 26.A leapfrog list starts 5, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 27.6 + 1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 =
- 28.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?
- 29.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?
- 30.4 + 2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 =
- 31.A leapfrog list starts 1, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 32.A leapfrog list starts 8, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 33.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?
- 34.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?
- 35.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?
- 36.Leapfrog list (each number is the sum of the two before it): 5, 5, 10, 15, 25, 40, 65, 105, 170, 275. What is 11 × the 7th number?
- 37.5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 + 254 + 411 =
- 38.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?
- 39.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?
- 40.2 + 1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 =
Answer key
- 759
- 704
- 517
- 847
- 1199
- 946
- 429
- 550
- 957
- 979
- 759
- 231
- 649
- 253
- 880
- 891
- 583
- 594
- 484
- 495
- 462
- 143
- 924
- 968
- 759
- 451
- 418
- 341
- 231
- 396
- 319
- 616
- 396
- 594
- 561
- 715
- 1067
- 462
- 1111
- 198
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks