Answer :
Answer:
Sum of G.P. series is given by,
Sum=
r−1
a(r
n
−1)
when r>1
Where a= first term, n=n
th
term and r is common ratio.
Here, a=1,n=10,r=
3
S
10
=
(
3
−1)
1×{(
3
)
10
−1}
=
(
3
−1)
(3
5
−1)
×
(
3
+1)
(
3
+1)
=
(3−1)
242(
3
+1)
=121(
3
+1).
