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The sum of first n terms of an AP is Sₙ = 3n² + 5n. Find the 4th term a₄.
A26
B44
C38
D32
Answer & Solution
Correct answer: A. 26
a₄ = S₄ − S₃ = (48 + 20) − (27 + 15) = 68 − 42 = 26.
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