Officer Preparation IQ Questions | Important Formula for Section Officer Exam 2074.

Hello guys in this post i’m going to share you the formula of series. Which is the important for officer question.

Question: What is the series of following question.

5,8,11,………………….320 Find out the series (tn) of number 320.

Formula: tn= a+(n-1)d

or 320=5+(n-1)3

or 320-5=3n-3

or 315+3=3n

or 318/3=n

Ans n=106  (320 comes on 106th in this series.)

Now lets Reverse the Question to Check the Answer.

Q. Where 5,8,11,14…………..Find out the number which comes at 106th of this series?

Formula: tn= a+(n-1)d

or tn= 5+(106-1)3

or tn= 5+(105)3

or tn= 5+315

Ans Tn=320 (In this series 320 comes on 106th position.

Please Share If it helps you.