Question

Find the $9^{th}$ term of an A.P.:

$2,5,8,11,.....$.

Answer 1

Given A.P. is $2,5,8,11,....$
$a=t_1=2,t_2=5,t_3=8$. .....
Common difference, $d=t_2-t_1=5-2=3$
Now, $t_n=a+(n-1)d$
Thus, $9$th term,
$t_9=2+(9-1)3$
$=2+8\times 3$
$=2+24$
$=26$.