Question

Let a₁, a₂, a₃, ....,$a_n$, be in A.P. If a₃ + a₇ + a₁₁ + a₁₅ = 72, then the sum of its first 17 terms is equal to :
(a) 306
(b) 204
(c) 153
(d) 612

Answer 1

the answer of your question IS

(c) 153.