Bunuel wrote:
If the sum of the 4th term and the 12th term of an arithmetic progression is 8, what is the sum of the first 15 terms of the progression?
A. 60
B. 120
C. 160
D. 240
E. 840
Kudos for a correctsolution.
Asked: If the sum of the 4th term and the 12th term of an arithmetic progression is 8, what is the sum of the first 15 terms of the progression?
(a + 3d) + (a +11d) = 8
2a + 14d = 8
Sum of first 15 terms = (15/2) (8) = 60
IMO A
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