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.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?
- 3.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?
- 4.Leapfrog list (each number is the sum of the two before it): 3, 3, 6, 9, 15, 24, 39, 63, 102, 165. What is 11 × the 7th number?
- 5.A leapfrog list starts 1, 5 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): 6, 2, 8, 10, 18, 28, 46, 74, 120, 194. What is 11 × the 7th number?
- 7.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?
- 8.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?
- 9.4 + 4 + 8 + 12 + 20 + 32 + 52 + 84 + 136 + 220 =
- 10.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?
- 11.7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 + 259 + 419 =
- 12.3 + 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 =
- 13.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?
- 14.3 + 3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 =
- 15.3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 =
- 16.Leapfrog list (each number is the sum of the two before it): 6, 8, 14, 22, 36, 58, 94, 152, 246, 398. What is 11 × the 7th number?
- 17.6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 + 225 + 364 =
- 18.A leapfrog list starts 5, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 19.4 + 1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 =
- 20.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
- 21.3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 + 233 =
- 22.Leapfrog list (each number is the sum of the two before it): 5, 7, 12, 19, 31, 50, 81, 131, 212, 343. What is 11 × the 7th number?
- 23.1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 =
- 24.A leapfrog list starts 3, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 25.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?
- 26.A leapfrog list starts 4, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 27.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?
- 28.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?
- 29.1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 + 259 =
- 30.3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 =
- 31.A leapfrog list starts 6, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 32.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?
- 33.7 + 6 + 13 + 19 + 32 + 51 + 83 + 134 + 217 + 351 =
- 34.A leapfrog list starts 5, 1 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): 3, 5, 8, 13, 21, 34, 55, 89, 144, 233. What is 11 × the 7th number?
- 36.Leapfrog list (each number is the sum of the two before it): 7, 4, 11, 15, 26, 41, 67, 108, 175, 283. What is 11 × the 7th number?
- 37.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?
- 38.5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 + 254 + 411 =
- 39.8 + 7 + 15 + 22 + 37 + 59 + 96 + 155 + 251 + 406 =
- 40.A leapfrog list starts 9, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
Answer key
- 374
- 671
- 1001
- 429
- 495
- 506
- 1199
- 374
- 572
- 451
- 1089
- 253
- 495
- 429
- 693
- 1034
- 946
- 539
- 308
- 781
- 605
- 891
- 759
- 781
- 759
- 1012
- 770
- 396
- 671
- 517
- 1034
- 528
- 913
- 363
- 605
- 737
- 143
- 1067
- 1056
- 1111
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks