1
You visited us
1
times! Enjoying our articles?
Unlock Full Access!
Byju's Answer
Standard XII
Mathematics
Arithmetic Progression
Find a1+a6+...
Question
Find
a
1
+
a
6
+
a
11
+
a
16
if it is known that
a
1
,
a
2
.
.
.
.
is an A.P. and
a
1
+
a
4
+
a
7
+
.
.
.
+
a
16
=
147.
Open in App
Solution
We have
a
1
,
a
2
,
.
.
.
in A.P. with common difference d.
So,
a
1
+
a
4
+
a
7
+
.
.
.
a
16
=
147
⇒
a
1
+
(
a
1
+
3
d
)
+
.
.
.
+
(
a
1
+
15
d
)
=
147
⇒
6
a
1
+
3
d
(
1
+
2
+
.
.
.
+
5
)
=
147
⇒
6
a
1
+
45
d
=
147
⇒
2
a
1
+
15
d
=
49
Now,
a
1
+
a
6
+
a
11
+
a
16
=
4
a
1
+
30
d
=
2
(
2
a
1
+
15
d
)
=
98
Suggest Corrections
0
Similar questions
Q.
Find
a
1
+
a
6
+
a
11
+
a
16
if it is known that
a
1
,
a
2
, ___________ is an A.P. and
a
1
+
a
4
+
a
7
+
a
10
+
a
13
+
a
16
=
147
.
Q.
If
a
n
is an A.P and
a
1
+
a
4
+
a
7
+
.
.
.
+
a
16
=
147
, then
a
1
+
a
6
+
a
11
+
a
16
=
Q.
If it is known that
a
1
+
a
4
+
a
7
+
a
10
+
a
13
+
a
16
=
147
then
a
1
+
a
6
+
a
11
+
a
16
=
Q.
If
a
1
,
a
2
,
a
3
,
⋯
,
a
n
are in A.P. and
a
1
+
a
4
+
a
7
+
⋯
+
a
16
=
114
, then
a
1
+
a
6
+
a
11
+
a
16
is equal to :
Q.
The sum of the first nineteen terms of an A.P.
a
1
,
a
2
,
a
3
.......... if it is known that
a
4
+
a
8
+
a
12
+
a
16
=
224
is .......... .
View More
Join BYJU'S Learning Program
Grade/Exam
1st Grade
2nd Grade
3rd Grade
4th Grade
5th Grade
6th grade
7th grade
8th Grade
9th Grade
10th Grade
11th Grade
12th Grade
Submit
Related Videos
Arithmetic Progression
MATHEMATICS
Watch in App
Explore more
Arithmetic Progression
Standard XII Mathematics
Join BYJU'S Learning Program
Grade/Exam
1st Grade
2nd Grade
3rd Grade
4th Grade
5th Grade
6th grade
7th grade
8th Grade
9th Grade
10th Grade
11th Grade
12th Grade
Submit
AI Tutor
Textbooks
Question Papers
Install app