Select the one which is different from the other three alternatives.
2017
Select the one which is different from the other three alternatives.
- A.
BCKL
- B.
LNST
- C.
EFNO
- D.
HIQR
Attempted by 29 students.
Show answer & explanation
Correct answer: B
Concept
In an odd-one-out letter series, three of the four groups share one hidden positional rule and one group breaks it. Convert each letter to its alphabet position (A=1, B=2, ... Z=26), then read the GAPS between consecutive letters within each group. The group whose gap pattern does not match the others is the answer.
Application
Mapping each group to alphabet positions and reading the internal gaps:
Group | Positions | Gaps |
|---|---|---|
BCKL | 2, 3, 11, 12 | +1, +8, +1 |
LNST | 12, 14, 19, 20 | +2, +5, +1 |
EFNO | 5, 6, 14, 15 | +1, +8, +1 |
HIQR | 8, 9, 17, 18 | +1, +8, +1 |
The shared rule is the gap pattern +1, +8, +1: a consecutive pair, then a jump of 8, then another consecutive pair (equivalently the 3rd letter is the 1st + 9 and the 4th is the 2nd + 9). BCKL, EFNO and HIQR all obey this rule.
Cross-check
LNST gives gaps +2, +5, +1: its first two letters L and N are not consecutive and the middle jump is 5, not 8. It is the only group that fails the +1, +8, +1 rule, so the correct answer is LNST.