Find the sum of the first n terms of the following arithmetic sequence.
-$91,174,257 , \ldots ; \mathrm { n } = 10$
A) $- 4190$
B) $- 2825$
C) 4645
D) 4190

Question

Quizplus · Accepted Answer

The sum of the first n terms of an arithmetic sequence can be found using the formula $S_n = \frac{n}{2} [2a + (n-1)d]$, where $S_n$ is the sum of the first n terms, $a$ is the first term, $n$ is the number of terms, and $d$ is the common difference. Here, $a = 91$, $n = 10$, and $d = 174 - 91 = 83$. Plugging these values into the formula gives $S_{10} = \frac{10}{2} [2(91) + (10-1)83] = 5[182 + 747] = 5 \times 929 = 4645$.

Find the Sum of the First N Terms of the Following