Chapter 14 - Sequences, Series, and the Binomial Theorem - 14.2 Arithmetic Sequences and Series - 14.2 Exercise Set - Page 902: 14

$a_{23}=142$

In an arithmetic sequence, first we have to find the common difference, which can be calculated as the difference of any two subsequent terms: $d=a_2-a_1=16-10=6$ The n th term can be calculated as: $a_n=a_1+d\times(n-1)$ The 23rd term is: $a_{23}=10+6\times(23-1)=142$