Find tn for the A.P. 3,8,13,18,.....
A.P : 3,8,13,18,.....
Here , a = 3
d = t2 -t1
= 8 - 3
d = 5
tn = a + (n - 1)d
tn = 3 + (n - 1)5
= 5n - 2
tn = 5n - 2