Saved Bookmarks
| 1. |
Difference between the sum of the first 20 terms and the next 20 terms of ap 6 10 14 |
|
Answer» Answer: Term 1 is 6. The difference is 4. Term 20 is 6 + 19 x 4 = 82. Term 21 is 86. Term 40 is 6 + 39 x 4 = 162. The sum of the first 20 terms is 20/2 (6 + 82) = 880. The sum of the next 20 terms is 20/2 (86 + 162) = 2480. The difference of the sums is 2480 - 880 = 1600. Alternately the sum of all 40 terms is 40/2 (6 + 162) = 3360. The sum of the second 20 terms is 3360 - 880 = 2480. The difference is still 2480 - 880 = 1600. |
|