1
You visited us
1
times! Enjoying our articles?
Unlock Full Access!
Byju's Answer
Standard XII
Mathematics
nth Term of A.P
If the sum of...
Question
If the sum of
n
terms of an
A
.
P
. is
3
n
2
+
5
n
, then which of its term is
164
A
26
t
h
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
27
t
h
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
C
28
t
h
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
N
o
n
e
o
f
t
h
e
s
e
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is
B
27
t
h
Given,
S
n
=
3
n
2
+
5
n
S
1
=
3
+
5
=
8
=
a
S
2
=
3
(
2
)
2
+
5
(
2
)
=
22
=
a
1
+
a
2
⇒
8
+
a
2
=
22
⇒
a
2
=
14
d
=
a
2
−
a
1
=
14
−
8
=
6
Let
a
n
=
164
⇒
a
+
(
n
−
1
)
d
=
164
⇒
8
+
(
n
−
1
)
6
=
164
⇒
8
+
6
n
−
6
=
164
⇒
6
n
=
162
⇒
n
=
27
∴
27
t
h
term is
164
Suggest Corrections
1
Similar questions
Q.
The sum of n terms of an A.P. is 3n
2
+ 5n, then 164 is its
(a) 24
th
term
(b) 27
th
term
(c) 26
th
term
(d) 25
th
term