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
- 1.5 + 1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 =
- 2.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
- 3.Leapfrog list (each number is the sum of the two before it): 1, 2, 3, 5, 8, 13, 21, 34, 55, 89. What is 11 × the 7th number?
- 4.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?
- 5.8 + 2 + 10 + 12 + 22 + 34 + 56 + 90 + 146 + 236 =
- 6.6 + 5 + 11 + 16 + 27 + 43 + 70 + 113 + 183 + 296 =
- 7.9 + 1 + 10 + 11 + 21 + 32 + 53 + 85 + 138 + 223 =
- 8.3 + 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 =
- 9.A leapfrog list starts 6, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 10.3 + 2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 =
- 11.Leapfrog list (each number is the sum of the two before it): 9, 9, 18, 27, 45, 72, 117, 189, 306, 495. What is 11 × the 7th number?
- 12.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?
- 13.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?
- 14.9 + 5 + 14 + 19 + 33 + 52 + 85 + 137 + 222 + 359 =
- 15.2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 =
- 16.5 + 3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 =
- 17.9 + 2 + 11 + 13 + 24 + 37 + 61 + 98 + 159 + 257 =
- 18.9 + 7 + 16 + 23 + 39 + 62 + 101 + 163 + 264 + 427 =
- 19.A leapfrog list starts 2, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 20.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?
- 21.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?
- 22.2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 =
- 23.Leapfrog list (each number is the sum of the two before it): 3, 4, 7, 11, 18, 29, 47, 76, 123, 199. What is 11 × the 7th number?
- 24.A leapfrog list starts 2, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 25.4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 + 254 =
- 26.A leapfrog list starts 4, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 27.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?
- 28.4 + 8 + 12 + 20 + 32 + 52 + 84 + 136 + 220 + 356 =
- 29.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?
- 30.Leapfrog list (each number is the sum of the two before it): 4, 6, 10, 16, 26, 42, 68, 110, 178, 288. What is 11 × the 7th number?
- 31.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?
- 32.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?
- 33.6 + 6 + 12 + 18 + 30 + 48 + 78 + 126 + 204 + 330 =
- 34.8 + 3 + 11 + 14 + 25 + 39 + 64 + 103 + 167 + 270 =
- 35.4 + 2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 =
- 36.7 + 6 + 13 + 19 + 32 + 51 + 83 + 134 + 217 + 351 =
- 37.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?
- 38.A leapfrog list starts 3, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 39.A leapfrog list starts 7, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 40.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?
Answer key
- 363
- 781
- 231
- 671
- 616
- 770
- 583
- 253
- 1122
- 341
- 1287
- 671
- 957
- 935
- 374
- 539
- 671
- 1111
- 638
- 341
- 726
- 550
- 517
- 286
- 660
- 572
- 638
- 924
- 704
- 748
- 715
- 594
- 858
- 704
- 396
- 913
- 693
- 253
- 913
- 913
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks