Alphabet series – fill the next three entries Sequence: A, B, N, C, D, O, E, F, P, ?, ?, ?
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AG, H, I
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BG, H, J
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CG, H, Q
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DJ, K, L
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EH, I, Q
Answer
Correct Answer: G, H, Q
Explanation
Introduction / Context:This sequence interleaves two patterns: a straightforward alphabetical run and a second track that inserts a different letter at every third position. Recognizing the interleaving is the key.
Given Data / Assumptions:
- Given order: A, B, N, C, D, O, E, F, P, ?, ?, ?
- English alphabet, no wrap-around needed.
- We must fill positions 10, 11, and 12.
Concept / Approach:Look at positions modulo 3. Every third term (3rd, 6th, 9th, …) appears to follow one subsequence, while the non-multiples of three follow another (a simple alphabetical sequence).
Step-by-Step Solution:
Main run (non-multiples of 3): A(1), B(2), then C(3), D(4), then E(5), F(6), then G(7), H(8), … These occupy positions 1–2, 4–5, 7–8, 10–11, … Thus positions 10 and 11 should be G and H.Inserted run (multiples of 3): At positions 3, 6, 9 we have N, O, P, which is a simple alphabetical sequence starting at N and increasing by 1. Therefore position 12 (next multiple of 3) should be Q.Hence the three missing entries are G, H, Q.Verification / Alternative check:List the two streams separately: Stream A: A, B, C, D, E, F, G, H; Stream B: N, O, P, Q at positions 3, 6, 9, 12. Merging them matches the original pattern and yields G, H, Q for the last three slots.
Why Other Options Are Wrong:
- G, H, I or G, H, J: the 12th position must continue N→O→P→Q, not I or J.
- J, K, L: ignores the ongoing alphabetical main stream and the special third-position inserts.
Common Pitfalls:Failing to notice the repeating 1–2–insert rhythm; trying to enforce one uniform rule across all positions.
Final Answer:G, H, Q