After 4th term, series start repeating itself. 5th term =1st term and 2nd term =6th term...going like this..
You have pasted the image so not able to see the ques bt solution is like this..if series is repeating itself after every 4th term..Till 96 terms..Seq. will have sum of 1st 4 numbers*24 and add the 97th term in that..you ll get the answer.

So, Adding 1st 4 terms sum is 3....till 96 terms...these are repeating itself..so as per solution above multiply with 24 and adding 97th term
(3*24)+2 = 74..........is the answer.

a1=2
a2=-3
a3=5
a4=-1

Since a5 and higher have the same values as 4 terms before it i.e a5 has a1 value; a6 has a2 value etcc

97 terms to find the sum for

96 / 4 = 24 and the 97th term will have a1's value

So there will 25 a1 values, 24 a2 values,24 a3values and 24 a4values

= 25(2)+24(-3)+24*5+24*-1
= 50-72+120-24
= 74

B)
OA?

THanks guys! OA - B.