Find the sum of the first 50 terms in an arithmetic series that has first term - 13 and 50th term 134

The sum of the arithmetic series has a formula of
S = (n/2)(a₁ + aₙ)
where
n = number of terms
a₁ = first term
aₙ = last term or nth term

Given n = 50, a₁ = -13, aₙ = 134. The sum is
S = (50/2)(-13 + 134)
S = 3025 (ANSWER)

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