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
- 1.6 + 5 + 11 + 16 + 27 + 43 + 70 + 113 + 183 + 296 =
- 2.9 + 1 + 10 + 11 + 21 + 32 + 53 + 85 + 138 + 223 =
- 3.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?
- 4.8 + 4 + 12 + 16 + 28 + 44 + 72 + 116 + 188 + 304 =
- 5.Leapfrog list (each number is the sum of the two before it): 6, 8, 14, 22, 36, 58, 94, 152, 246, 398. What is 11 × the 7th number?
- 6.5 + 1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 =
- 7.Leapfrog list (each number is the sum of the two before it): 1, 7, 8, 15, 23, 38, 61, 99, 160, 259. What is 11 × the 7th number?
- 8.7 + 2 + 9 + 11 + 20 + 31 + 51 + 82 + 133 + 215 =
- 9.9 + 6 + 15 + 21 + 36 + 57 + 93 + 150 + 243 + 393 =
- 10.1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 + 225 =
- 11.7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 + 280 + 453 =
- 12.6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 + 267 + 432 =
- 13.A leapfrog list starts 3, 6 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 14.Leapfrog list (each number is the sum of the two before it): 7, 7, 14, 21, 35, 56, 91, 147, 238, 385. What is 11 × the 7th number?
- 15.Leapfrog list (each number is the sum of the two before it): 3, 8, 11, 19, 30, 49, 79, 128, 207, 335. What is 11 × the 7th number?
- 16.Leapfrog list (each number is the sum of the two before it): 7, 5, 12, 17, 29, 46, 75, 121, 196, 317. What is 11 × the 7th number?
- 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 9, 9 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): 2, 5, 7, 12, 19, 31, 50, 81, 131, 212. What is 11 × the 7th number?
- 20.3 + 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 =
- 21.Leapfrog list (each number is the sum of the two before it): 9, 6, 15, 21, 36, 57, 93, 150, 243, 393. What is 11 × the 7th number?
- 22.6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 + 246 + 398 =
- 23.3 + 2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 =
- 24.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?
- 25.A leapfrog list starts 9, 2 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 26.1 + 1 + 2 + 3 + 5 + 8 + 13 + 21 + 34 + 55 =
- 27.6 + 3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 =
- 28.9 + 5 + 14 + 19 + 33 + 52 + 85 + 137 + 222 + 359 =
- 29.4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 + 199 + 322 =
- 30.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?
- 31.8 + 5 + 13 + 18 + 31 + 49 + 80 + 129 + 209 + 338 =
- 32.Leapfrog list (each number is the sum of the two before it): 9, 4, 13, 17, 30, 47, 77, 124, 201, 325. What is 11 × the 7th number?
- 33.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?
- 34.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?
- 35.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
- 36.Leapfrog list (each number is the sum of the two before it): 2, 3, 5, 8, 13, 21, 34, 55, 89, 144. What is 11 × the 7th number?
- 37.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?
- 38.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?
- 39.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?
- 40.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?
Answer key
- 770
- 583
- 253
- 792
- 1034
- 363
- 671
- 561
- 1023
- 583
- 1177
- 1122
- 693
- 1001
- 869
- 825
- 737
- 1287
- 550
- 253
- 1023
- 1034
- 341
- 308
- 671
- 143
- 594
- 935
- 836
- 198
- 880
- 847
- 418
- 759
- 781
- 374
- 1287
- 627
- 957
- 913
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks