Answer
$a_{18}=178$
Work Step by Step
The n th term of an arithmetic sequence can be calculated as:
$a_n=a_1+d\times(n-1)$
Here: $n=18$, $d=10$ and we have to find $a_{18}$.
By substituting we get:
$a_{18}=8+10\times(18-1)=178$
$a_{18}=178$