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.Leapfrog list (each number is the sum of the two before it): 4, 1, 5, 6, 11, 17, 28, 45, 73, 118. What is 11 × the 7th number?
- 2.1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 + 225 =
- 3.5 + 1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 =
- 4.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?
- 5.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?
- 6.8 + 4 + 12 + 16 + 28 + 44 + 72 + 116 + 188 + 304 =
- 7.1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 =
- 8.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?
- 9.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?
- 10.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?
- 11.3 + 2 + 5 + 7 + 12 + 19 + 31 + 50 + 81 + 131 =
- 12.6 + 6 + 12 + 18 + 30 + 48 + 78 + 126 + 204 + 330 =
- 13.6 + 3 + 9 + 12 + 21 + 33 + 54 + 87 + 141 + 228 =
- 14.6 + 2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 =
- 15.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?
- 16.1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 + 191 =
- 17.Leapfrog list (each number is the sum of the two before it): 6, 1, 7, 8, 15, 23, 38, 61, 99, 160. What is 11 × the 7th number?
- 18.Leapfrog list (each number is the sum of the two before it): 5, 7, 12, 19, 31, 50, 81, 131, 212, 343. What is 11 × the 7th number?
- 19.A leapfrog list starts 9, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 20.Leapfrog list (each number is the sum of the two before it): 1, 4, 5, 9, 14, 23, 37, 60, 97, 157. What is 11 × the 7th number?
- 21.3 + 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 =
- 22.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?
- 23.Leapfrog list (each number is the sum of the two before it): 3, 3, 6, 9, 15, 24, 39, 63, 102, 165. What is 11 × the 7th number?
- 24.Leapfrog list (each number is the sum of the two before it): 6, 5, 11, 16, 27, 43, 70, 113, 183, 296. What is 11 × the 7th number?
- 25.A leapfrog list starts 3, 8 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 3, 5 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 27.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
- 28.4 + 1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 =
- 29.6 + 4 + 10 + 14 + 24 + 38 + 62 + 100 + 162 + 262 =
- 30.A leapfrog list starts 8, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 31.A leapfrog list starts 8, 9 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 32.6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 + 246 + 398 =
- 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.Leapfrog list (each number is the sum of the two before it): 5, 5, 10, 15, 25, 40, 65, 105, 170, 275. What is 11 × the 7th number?
- 35.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?
- 36.8 + 1 + 9 + 10 + 19 + 29 + 48 + 77 + 125 + 202 =
- 37.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?
- 38.7 + 6 + 13 + 19 + 32 + 51 + 83 + 134 + 217 + 351 =
- 39.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?
- 40.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?
Answer key
- 308
- 583
- 363
- 693
- 825
- 792
- 319
- 550
- 319
- 759
- 341
- 858
- 594
- 506
- 561
- 495
- 418
- 891
- 1199
- 407
- 253
- 803
- 429
- 770
- 869
- 605
- 781
- 308
- 682
- 1056
- 1232
- 1034
- 418
- 715
- 462
- 528
- 143
- 913
- 858
- 231
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks