Question

How to solve the sums there in this

Answer 1

Hey sorry to say this. But ur picture has no clarity at all.
Repost it.

Answer 2

tn=3+5n
putting the value of n starting from 1
a=3+5=8.
and then putting 2 like before
a2= 3+2(5)=3+10=13
from here we got the d
d= a2-a1
=13-8=5
do, d is= 5
now, I we have find to the AP of 21th term so, let do this
an= a+(n-1)d
=8+(21-1)5
=8+(20)5
=8+100
108