What numbers should replace the question marks if the same sequence has to be followed in the given series:
71, 81, 74, 77, 77, 73, 80, 69, ?, ?, ?, ?
(A) 65
(B) 86
(C) 61
(D) 83
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → (D), (A), (B), (C)
(D) 83
(A) 65
(B) 86
(C) 61
The series consists of two interleaved arithmetic progressions:
- The numbers in the odd positions (1st, 3rd, 5th, etc.) form a sequence that increases by 3 each time: 71, 74, 77, 80, 83, 86, ...
- The numbers in the even positions (2nd, 4th, 6th, etc.) form a sequence that decreases by 4 each time: 81, 77, 73, 69, 65, 61, ...
Combining these, the complete series is: 71, 81, 74, 77, 77, 73, 80, 69, 83, 65, 86, 61.