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 2, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 2.5 + 1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 =
- 3.1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 =
- 4.A leapfrog list starts 5, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 5.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?
- 6.1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 + 191 =
- 7.5 + 2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 =
- 8.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?
- 9.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?
- 10.1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 =
- 11.A leapfrog list starts 9, 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 4, 2 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?
- 14.4 + 3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 =
- 15.3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 + 369 =
- 16.Leapfrog list (each number is the sum of the two before it): 3, 1, 4, 5, 9, 14, 23, 37, 60, 97. What is 11 × the 7th number?
- 17.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?
- 18.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?
- 19.1 + 9 + 10 + 19 + 29 + 48 + 77 + 125 + 202 + 327 =
- 20.A leapfrog list starts 7, 9 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 9, 3 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 22.Leapfrog list (each number is the sum of the two before it): 8, 4, 12, 16, 28, 44, 72, 116, 188, 304. What is 11 × the 7th number?
- 23.Leapfrog list (each number is the sum of the two before it): 7, 1, 8, 9, 17, 26, 43, 69, 112, 181. What is 11 × the 7th number?
- 24.A leapfrog list starts 1, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 25.6 + 1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 =
- 26.2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 + 246 =
- 27.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?
- 28.7 + 2 + 9 + 11 + 20 + 31 + 51 + 82 + 133 + 215 =
- 29.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?
- 30.A leapfrog list starts 5, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 31.9 + 4 + 13 + 17 + 30 + 47 + 77 + 124 + 201 + 325 =
- 32.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?
- 33.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?
- 34.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?
- 35.Leapfrog list (each number is the sum of the two before it): 9, 7, 16, 23, 39, 62, 101, 163, 264, 427. What is 11 × the 7th number?
- 36.9 + 5 + 14 + 19 + 33 + 52 + 85 + 137 + 222 + 359 =
- 37.1 + 1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 =
- 38.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?
- 39.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?
- 40.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?
Answer key
- 286
- 363
- 319
- 627
- 253
- 495
- 451
- 583
- 341
- 759
- 935
- 396
- 1287
- 484
- 957
- 253
- 143
- 407
- 847
- 1177
- 759
- 792
- 473
- 759
- 418
- 638
- 682
- 561
- 627
- 1067
- 847
- 539
- 572
- 803
- 1111
- 935
- 143
- 1122
- 495
- 726
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks