Use the Formula for the Sum of the First n Terms of an Arithmetic Sequence
-Find the sum of the odd integers between 114 and 60.
A)2349
B)2359
C)4872
D)2364

Question

Quizplus · Accepted Answer

The sum of the odd integers between 114 and 60 can be found using the formula for the sum of an arithmetic sequence, $S = \frac{n}{2}(a_1 + a_n)$, where $n$ is the number of terms, $a_1$ is the first term, and $a_n$ is the last term. The first odd integer after 60 is 61, and the last odd integer before 114 is 113. To find $n$, we use the formula for the nth term of an arithmetic sequence, $a_n = a_1 + (n - 1)d$, where $d$ is the common difference, which is 2 for odd integers. Solving for $n$ gives us $n = \frac{113 - 61}{2} + 1 = 27$. Plugging into the sum formula, $S = \frac{27}{2}(61 + 113) = 2349$.

Use the Formula for the Sum of the First N