What should come in place of question mark (?) in the given series based on…
2025
What should come in place of question mark (?) in the given series based on English alphabetical order?
SUB OQX KMT GIP ?
- A.
CDR
- B.
CDE
- C.
CLE
- D.
CEL
Attempted by 6 students.
Show answer & explanation
Correct answer: D
Concept: In an alphabet-position series, replace each letter by its place in the alphabet (A = 1 ... Z = 26). When the corresponding letters across consecutive terms -- 1st letters together, 2nd letters together, 3rd letters together -- change by the same fixed amount each time, that column follows a constant arithmetic step; if subtracting the step takes the value below 1, wrap around the alphabet (continue counting backward from Z).
Term | 1st letter (value) | 2nd letter (value) | 3rd letter (value) |
|---|---|---|---|
SUB | S (19) | U (21) | B (2) |
OQX | O (15) | Q (17) | X (24) |
KMT | K (11) | M (13) | T (20) |
GIP | G (7) | I (9) | P (16) |
? | C (3) | E (5) | L (12) |
Convert every letter of SUB, OQX, KMT, GIP to its alphabet position, column by column, as shown in the table above.
Column 1 (S, O, K, G = 19, 15, 11, 7) decreases by 4 each term; Column 2 (U, Q, M, I = 21, 17, 13, 9) decreases by 4 each term; Column 3 (B, X, T, P = 2, 24, 20, 16) also decreases by 4 each term once the wrap past A back to Z is accounted for (2 - 4 = -2, and -2 + 26 = 24).
Apply the same step of -4 to the last term's three columns: 7 - 4 = 3 -> C; 9 - 4 = 5 -> E; 16 - 4 = 12 -> L.
Combine the three results in column order to get the next term: C, E, L -> CEL.
Cross-check: reversing the step (+4) on C, E, L should reproduce the previous term G, I, P. C(3)+4=7=G, E(5)+4=9=I, L(12)+4=16=P -- all three match, confirming the term was derived correctly.
So the series continues with CEL.