Find the missing term in the alphanumeric series: F2, __, D8, C16, B32, … Letters decrease by one alphabet step each time; numbers follow a consistent pattern. Choose the correct missing term.
Correct Answer: E4
Introduction / Context:Alphanumeric series combine letter progressions with number rules. Here, the letters descend alphabetically while the numbers grow by a simple deterministic pattern.
Given Data / Assumptions:
- Series: F2, ?, D8, C16, B32, …
- Exactly one term is missing after F2.
Concept / Approach:Inspect letters and numbers separately. Letters: F → E → D → C → B (each step moves one position backward in the alphabet). Numbers: 2 → 4 → 8 → 16 → 32 (each step doubles).
Step-by-Step Solution:From F2, the next letter is E and the next number is 2*2 = 4.Therefore, the missing term is E4.Continuing verifies: E4, D8, C16, B32.
Verification / Alternative check:Check both tracks independently: letters F,E,D,C,B (−1 each step); numbers 2,4,8,16,32 (×2 each step). Both tracks are consistent.
Why Other Options Are Wrong:
- A16 / G4 / E3: Each breaks either the backward-letter move or the doubling of numbers (E3 is not a doubling from 2).
Common Pitfalls:Trying to link letters and numbers into a single arithmetic rule rather than analyzing them independently.
Final Answer:E4