what is the sum of the arithmetic series 18 sigma t-1 (5t-4)?
Accepted Solution
A:
Answer:783Step-by-step explanation:We have to find the sum of Arithmetic series from t = 1 to t = 18 represented by (5t - 4)The formula to find the sum of an Arithmetic series when first and the last term is known is:[tex]S_{n}=\frac{n}{2}(a_{1}+a_{n})[/tex]Here,n = Total number of terms = 18[tex]a_{1}[/tex] = First Term = 5(1) - 4 = 1[tex]a_{18}[/tex] = 18th Term = 5(18) - 4 = 86Using the values in the above formula, we get:[tex]S_{18}=\frac{18}{2}(1+86)\\\\ S_{18}=9(87)\\\\ S_{18}=783[/tex]Thus, the sum of 18 terms of the given Arithmetic Series is 783.