Question

What is the sum of the series?
10
Σ(7k– 2)
k=1

Answer 1

365

Explanation:

The simplest method is to substitute values of k = 1 to 10 into the expression and sum the terms, that is

7(1) - 2 + 7(2) - 2 + 7(3) - 2 + 7(4) - 2 + 7(5) - 2 + 7(6) - 2 + 7(7) - 2 + 7(8) - 2 + 7(9) - 2 + 7(10) - 2

= 5 + 12 + 19 + 26 + 33 + 40 + 47 + 54 + 61 + 68

= 365