A sequence is numbers is written in the following position : 1,7,1,1,7,7,1,1,1,7,7,7, ------- till n terms
what is the value of
is the nth term of the given sequence.
4
28
10
22
As learnt in concept
Sequence -
Arragement of real numbers specified in a definite order, by some assigned law.
- wherein
Notations -
or
The number of terms that end are ;
2, 2+4, 2+4+6, 2+4+6+8.....
So we get,
2+4+6+8+....+n terms
=
Now,
Then,
and rest of the terms,
So,
Sum= 22
Option 1)
4
Incorrect option
Option 2)
28
Incorrect option
Option 3)
10
Incorrect option
Option 4)
22
correct option