Answer
$396$
Work Step by Step
Formula to calculate the sum of an arithmetic sequence is: $S_n=\dfrac{n}{2}(a_1+a_n)$ ...(1)
Here, $a_1: $ First term and $a_n=$last term
and $a_1: $ First even term is 22 and $a_n$:last term is 44, thus the total even terms are $12$.Then use equation (1) to get the sum of the sequence.
Thus, $S_{12}=\dfrac{12}{2}(22+44)\\=6(66)\\=396$
