Sequence and Series
Arithmetic Progression
JEE Main 2019
Grade 11
Question:
Let $S_n$ be the sum of first $n$ terms of an A.P. If $S_4 = 16$ and $S_6 = -48$, then $S_{10}$ is:
(1) $-320$
(2) $-260$
(3) $-340$
(4) $-420$
Step-by-Step Solution
Key Concept: Write $S_n = \frac{n}{2}(2a + (n - 1)d)$. Set up two equations using $S_4 = 16$ and $S_6 = -48$. Solve for $a$ and $d$, then compute $S_{10}$.
The detailed step-by-step mathematical proof is available inside the Mathbee app workspace.
Correct Answer: (1)