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 + 4 + 9 + 13 + 22 + 35 + 57 + 92 + 149 + 241 =
- 2.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?
- 3.Leapfrog list (each number is the sum of the two before it): 4, 7, 11, 18, 29, 47, 76, 123, 199, 322. What is 11 × the 7th number?
- 4.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?
- 5.2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 + 280 =
- 6.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?
- 7.Leapfrog list (each number is the sum of the two before it): 3, 2, 5, 7, 12, 19, 31, 50, 81, 131. What is 11 × the 7th number?
- 8.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?
- 9.7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 + 259 + 419 =
- 10.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?
- 11.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?
- 12.A leapfrog list starts 7, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 13.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?
- 14.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
- 15.3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 + 369 =
- 16.6 + 1 + 7 + 8 + 15 + 23 + 38 + 61 + 99 + 160 =
- 17.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?
- 18.9 + 6 + 15 + 21 + 36 + 57 + 93 + 150 + 243 + 393 =
- 19.6 + 3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 =
- 20.A leapfrog list starts 1, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 21.3 + 8 + 11 + 19 + 30 + 49 + 79 + 128 + 207 + 335 =
- 22.9 + 9 + 18 + 27 + 45 + 72 + 117 + 189 + 306 + 495 =
- 23.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?
- 24.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?
- 25.8 + 6 + 14 + 20 + 34 + 54 + 88 + 142 + 230 + 372 =
- 26.Leapfrog list (each number is the sum of the two before it): 2, 2, 4, 6, 10, 16, 26, 42, 68, 110. What is 11 × the 7th number?
- 27.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?
- 28.5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 + 212 + 343 =
- 29.A leapfrog list starts 2, 4 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 30.2 + 1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 =
- 31.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?
- 32.Leapfrog list (each number is the sum of the two before it): 6, 7, 13, 20, 33, 53, 86, 139, 225, 364. What is 11 × the 7th number?
- 33.6 + 2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 =
- 34.9 + 2 + 11 + 13 + 24 + 37 + 61 + 98 + 159 + 257 =
- 35.1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 + 225 =
- 36.A leapfrog list starts 5, 8 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 2, 1 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 38.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?
- 39.9 + 4 + 13 + 17 + 30 + 47 + 77 + 124 + 201 + 325 =
- 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
- 627
- 1067
- 836
- 143
- 726
- 583
- 341
- 451
- 1089
- 517
- 759
- 825
- 594
- 781
- 957
- 418
- 253
- 1023
- 594
- 143
- 869
- 1287
- 726
- 1287
- 968
- 286
- 594
- 891
- 462
- 198
- 913
- 946
- 506
- 671
- 583
- 979
- 198
- 627
- 847
- 693
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks