Question

Given t1 = -23, n = 25, and tn = 57, find the sum of the arithmetic series.
A. 125
B. 250
C. 325
D. 425

Answer 1

@zarkon @sammixboo

Answer 2

Please try this formula:
\[S = \frac{{{t_1} + {t_n}}}{2}n\]

Answer 3

where S is your sum