The sum of first 16 terms of the AP: 10, 6, 2, ... is ______.

Question

KollegeApply · Accepted Answer

The sum of first 16 terms of the AP: 10, 6, 2, ... is –320. Explanation: Given, AP is 10, 6, 2,... Here, First term a = 10, Common difference, d = – 4 $\therefore$ S16 = $\frac{16}{2}$[2a + (16 - 1)d] ...[∵ S_n = n/2[2a + (n - 1)d]] = 8[2 $\times$ 10 + 15(– 4)] = 8(20 – 60) = 8(– 40) = – 320

AChoose Your Answer