<h2>
The sum of the given series = 176</h2>
Step-by-step explanation:
The given series:

Here, first term(a) = 6 and common difference(d) = 8 - 6 = 2
The given series are in AP.
Let the number of term = n
We know that,
The nth term of an AP
∴ 
⇒ 6 + (n - 1) 2 = 26
⇒ (n - 1) 2 = 26 - 6 = 20
⇒ n - 1 = 
⇒ n = 10 + 1 = 11
∴ The sum of the given series = 
= 
= 
= 11 × 16 = 176
Thus, the sum of the given series = 176