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
- 1.7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 + 280 + 453 =
- 2.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?
- 3.8 + 4 + 12 + 16 + 28 + 44 + 72 + 116 + 188 + 304 =
- 4.9 + 7 + 16 + 23 + 39 + 62 + 101 + 163 + 264 + 427 =
- 5.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?
- 6.A leapfrog list starts 9, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 7.Leapfrog list (each number is the sum of the two before it): 2, 7, 9, 16, 25, 41, 66, 107, 173, 280. What is 11 × the 7th number?
- 8.3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 + 233 =
- 9.8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 + 474 =
- 10.1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 + 259 =
- 11.5 + 5 + 10 + 15 + 25 + 40 + 65 + 105 + 170 + 275 =
- 12.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?
- 13.6 + 1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 =
- 14.A leapfrog list starts 7, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 15.8 + 5 + 13 + 18 + 31 + 49 + 80 + 129 + 209 + 338 =
- 16.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?
- 17.A leapfrog list starts 7, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 18.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?
- 19.Leapfrog list (each number is the sum of the two before it): 4, 1, 5, 6, 11, 17, 28, 45, 73, 118. What is 11 × the 7th number?
- 20.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?
- 21.A leapfrog list starts 1, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 22.4 + 2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 =
- 23.7 + 7 + 14 + 21 + 35 + 56 + 91 + 147 + 238 + 385 =
- 24.8 + 6 + 14 + 20 + 34 + 54 + 88 + 142 + 230 + 372 =
- 25.1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 =
- 26.3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 + 335 =
- 27.5 + 3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 =
- 28.8 + 2 + 10 + 12 + 22 + 34 + 56 + 90 + 146 + 236 =
- 29.9 + 1 + 10 + 11 + 21 + 32 + 53 + 85 + 138 + 223 =
- 30.4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 + 178 + 288 =
- 31.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?
- 32.5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 + 233 + 377 =
- 33.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?
- 34.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?
- 35.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?
- 36.7 + 4 + 11 + 15 + 26 + 41 + 67 + 108 + 175 + 283 =
- 37.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?
- 38.Leapfrog list (each number is the sum of the two before it): 7, 8, 15, 23, 38, 61, 99, 160, 259, 419. What is 11 × the 7th number?
- 39.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?
- 40.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?
Answer key
- 1177
- 1199
- 792
- 1111
- 528
- 1023
- 726
- 605
- 1232
- 671
- 715
- 363
- 418
- 561
- 880
- 451
- 737
- 418
- 308
- 748
- 407
- 396
- 1001
- 968
- 407
- 869
- 539
- 616
- 583
- 748
- 594
- 979
- 506
- 341
- 286
- 737
- 1144
- 1089
- 319
- 693
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks