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): 3, 1, 4, 5, 9, 14, 23, 37, 60, 97. What is 11 × the 7th number?
- 2.3 + 7 + 10 + 17 + 27 + 44 + 71 + 115 + 186 + 301 =
- 3.2 + 6 + 8 + 14 + 22 + 36 + 58 + 94 + 152 + 246 =
- 4.6 + 2 + 8 + 10 + 18 + 28 + 46 + 74 + 120 + 194 =
- 5.A leapfrog list starts 8, 8 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 6.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?
- 7.Leapfrog list (each number is the sum of the two before it): 8, 5, 13, 18, 31, 49, 80, 129, 209, 338. What is 11 × the 7th number?
- 8.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?
- 9.A leapfrog list starts 6, 2 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 7, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 11.1 + 8 + 9 + 17 + 26 + 43 + 69 + 112 + 181 + 293 =
- 12.8 + 2 + 10 + 12 + 22 + 34 + 56 + 90 + 146 + 236 =
- 13.Leapfrog list (each number is the sum of the two before it): 2, 4, 6, 10, 16, 26, 42, 68, 110, 178. What is 11 × the 7th number?
- 14.Leapfrog list (each number is the sum of the two before it): 2, 6, 8, 14, 22, 36, 58, 94, 152, 246. What is 11 × the 7th number?
- 15.Leapfrog list (each number is the sum of the two before it): 6, 2, 8, 10, 18, 28, 46, 74, 120, 194. What is 11 × the 7th number?
- 16.2 + 7 + 9 + 16 + 25 + 41 + 66 + 107 + 173 + 280 =
- 17.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?
- 18.1 + 9 + 10 + 19 + 29 + 48 + 77 + 125 + 202 + 327 =
- 19.5 + 1 + 6 + 7 + 13 + 20 + 33 + 53 + 86 + 139 =
- 20.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?
- 21.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?
- 22.8 + 1 + 9 + 10 + 19 + 29 + 48 + 77 + 125 + 202 =
- 23.8 + 8 + 16 + 24 + 40 + 64 + 104 + 168 + 272 + 440 =
- 24.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?
- 25.1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97 + 157 =
- 26.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?
- 27.9 + 6 + 15 + 21 + 36 + 57 + 93 + 150 + 243 + 393 =
- 28.Leapfrog list (each number is the sum of the two before it): 2, 8, 10, 18, 28, 46, 74, 120, 194, 314. What is 11 × the 7th number?
- 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.Leapfrog list (each number is the sum of the two before it): 2, 1, 3, 4, 7, 11, 18, 29, 47, 76. What is 11 × the 7th number?
- 31.Leapfrog list (each number is the sum of the two before it): 1, 8, 9, 17, 26, 43, 69, 112, 181, 293. What is 11 × the 7th number?
- 32.1 + 5 + 6 + 11 + 17 + 28 + 45 + 73 + 118 + 191 =
- 33.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?
- 34.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?
- 35.9 + 4 + 13 + 17 + 30 + 47 + 77 + 124 + 201 + 325 =
- 36.3 + 3 + 6 + 9 + 15 + 24 + 39 + 63 + 102 + 165 =
- 37.1 + 3 + 4 + 7 + 11 + 18 + 29 + 47 + 76 + 123 =
- 38.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?
- 39.A leapfrog list starts 9, 7 and each next number is the sum of the two before it. What do the first 10 numbers add up to?
- 40.5 + 4 + 9 + 13 + 22 + 35 + 57 + 92 + 149 + 241 =
Answer key
- 253
- 781
- 638
- 506
- 1144
- 1232
- 880
- 902
- 506
- 1001
- 759
- 616
- 462
- 638
- 506
- 726
- 462
- 847
- 363
- 671
- 407
- 528
- 1144
- 407
- 407
- 308
- 1023
- 814
- 627
- 198
- 759
- 495
- 1199
- 594
- 847
- 429
- 319
- 660
- 1111
- 627
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks