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.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?
- 2.5 + 2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 =
- 3.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?
- 4.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?
- 5.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?
- 6.A leapfrog list starts 4, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 7.4 + 8 + 12 + 20 + 32 + 52 + 84 + 136 + 220 + 356 =
- 8.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?
- 9.A leapfrog list starts 9, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 10.6 + 4 + 10 + 14 + 24 + 38 + 62 + 100 + 162 + 262 =
- 11.A leapfrog list starts 2, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 12.A leapfrog list starts 7, 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): 9, 9, 18, 27, 45, 72, 117, 189, 306, 495. What is 11 × the 7th number?
- 14.3 + 3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 =
- 15.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?
- 16.A leapfrog list starts 3, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 17.6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 + 246 + 398 =
- 18.Leapfrog list (each number is the sum of the two before it): 6, 6, 12, 18, 30, 48, 78, 126, 204, 330. What is 11 × the 7th number?
- 19.9 + 5 + 14 + 19 + 33 + 52 + 85 + 137 + 222 + 359 =
- 20.Leapfrog list (each number is the sum of the two before it): 8, 7, 15, 22, 37, 59, 96, 155, 251, 406. What is 11 × the 7th number?
- 21.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?
- 22.4 + 6 + 10 + 16 + 26 + 42 + 68 + 110 + 178 + 288 =
- 23.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?
- 24.Leapfrog list (each number is the sum of the two before it): 5, 6, 11, 17, 28, 45, 73, 118, 191, 309. What is 11 × the 7th number?
- 25.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?
- 26.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?
- 27.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?
- 28.7 + 7 + 14 + 21 + 35 + 56 + 91 + 147 + 238 + 385 =
- 29.2 + 9 + 11 + 20 + 31 + 51 + 82 + 133 + 215 + 348 =
- 30.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?
- 31.2 + 1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 =
- 32.8 + 4 + 12 + 16 + 28 + 44 + 72 + 116 + 188 + 304 =
- 33.A leapfrog list starts 8, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 34.Leapfrog list (each number is the sum of the two before it): 4, 2, 6, 8, 14, 22, 36, 58, 94, 152. What is 11 × the 7th number?
- 35.2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 + 89 + 144 =
- 36.2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 =
- 37.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?
- 38.4 + 1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 =
- 39.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?
- 40.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?
Answer key
- 1122
- 451
- 495
- 319
- 1199
- 308
- 924
- 495
- 583
- 682
- 550
- 649
- 1287
- 429
- 528
- 957
- 1034
- 858
- 935
- 1056
- 748
- 748
- 528
- 803
- 253
- 231
- 561
- 1001
- 902
- 561
- 198
- 792
- 968
- 396
- 374
- 550
- 539
- 308
- 451
- 638
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks