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 1, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 2.9 + 5 + 14 + 19 + 33 + 52 + 85 + 137 + 222 + 359 =
- 3.3 + 3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 =
- 4.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?
- 5.A leapfrog list starts 5, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 6.6 + 4 + 10 + 14 + 24 + 38 + 62 + 100 + 162 + 262 =
- 7.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?
- 8.7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 + 259 + 419 =
- 9.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?
- 10.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?
- 11.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?
- 12.9 + 9 + 18 + 27 + 45 + 72 + 117 + 189 + 306 + 495 =
- 13.Leapfrog list (each number is the sum of the two before it): 9, 1, 10, 11, 21, 32, 53, 85, 138, 223. What is 11 × the 7th number?
- 14.Leapfrog list (each number is the sum of the two before it): 6, 4, 10, 14, 24, 38, 62, 100, 162, 262. What is 11 × the 7th number?
- 15.Leapfrog list (each number is the sum of the two before it): 4, 9, 13, 22, 35, 57, 92, 149, 241, 390. What is 11 × the 7th number?
- 16.4 + 8 + 12 + 20 + 32 + 52 + 84 + 136 + 220 + 356 =
- 17.1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 =
- 18.5 + 3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 =
- 19.9 + 3 + 12 + 15 + 27 + 42 + 69 + 111 + 180 + 291 =
- 20.A leapfrog list starts 4, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 21.4 + 2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 =
- 22.9 + 1 + 10 + 11 + 21 + 32 + 53 + 85 + 138 + 223 =
- 23.A leapfrog list starts 1, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 24.7 + 1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 =
- 25.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?
- 26.A leapfrog list starts 2, 9 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): 5, 4, 9, 13, 22, 35, 57, 92, 149, 241. What is 11 × the 7th number?
- 28.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?
- 29.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?
- 30.9 + 7 + 16 + 23 + 39 + 62 + 101 + 163 + 264 + 427 =
- 31.A leapfrog list starts 6, 4 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): 9, 9, 18, 27, 45, 72, 117, 189, 306, 495. What is 11 × the 7th number?
- 33.8 + 6 + 14 + 20 + 34 + 54 + 88 + 142 + 230 + 372 =
- 34.Leapfrog list (each number is the sum of the two before it): 4, 5, 9, 14, 23, 37, 60, 97, 157, 254. What is 11 × the 7th number?
- 35.Leapfrog list (each number is the sum of the two before it): 7, 3, 10, 13, 23, 36, 59, 95, 154, 249. What is 11 × the 7th number?
- 36.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?
- 37.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?
- 38.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?
- 39.3 + 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 =
- 40.3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 =
Answer key
- 495
- 935
- 429
- 968
- 803
- 682
- 143
- 1089
- 770
- 913
- 803
- 1287
- 583
- 682
- 1012
- 924
- 759
- 539
- 759
- 836
- 396
- 583
- 847
- 473
- 957
- 902
- 627
- 517
- 374
- 1111
- 682
- 1287
- 968
- 660
- 649
- 583
- 968
- 594
- 253
- 693
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks