Based on the English alphabetical order, three of the following four letter-cluster pairs are alike in a certain way and thus form a group. Which letter-cluster pair DOES NOT belong to that group? (Note: The odd one out is not based on the number of consonants/vowels or their position in the letter cluster)

Question

Prepp Team · Accepted Answer

Letter Cluster Analysis for Reasoning

This question challenges us to identify which pair of letter clusters stands apart from the rest based on a specific pattern related to the English alphabet. Three pairs will share a common characteristic, while one will not.

Alphabetical Order Pattern Recognition

The key to solving this is understanding the sequence and relationships between letters in the standard English alphabet (A=1, B=2, ..., Z=26). We need to look for consistent rules governing the letter pairs provided in each option.

Letter Pair Comparisons

Let's examine each option by mapping the letters to their alphabetical positions and analyzing the differences:

Option	Pair 1 Letters	Pair 1 Positions	Pair 2 Letters	Pair 2 Positions	Pattern Analysis
1. QR - WX	QR	Q ($17$), R ($18$)	WX	W ($23$), X ($24$)	Q and R are consecutive: $18 - 17 = 1$. W and X are consecutive: $24 - 23 = 1$. Offset Q $\rightarrow$ W: $23 - 17 = 6$. Offset R $\rightarrow$ X: $24 - 18 = 6$. Commonality: Both pairs use consecutive letters, and the second pair is shifted by 6 positions.
2. LM - RS	LM	L ($12$), M ($13$)	RS	R ($18$), S ($19$)	L and M are consecutive: $13 - 12 = 1$. R and S are consecutive: $19 - 18 = 1$. Offset L $\rightarrow$ R: $18 - 12 = 6$. Offset M $\rightarrow$ S: $19 - 13 = 6$. Commonality: Matches the pattern of option 1.
3. ST - YZ	ST	S ($19$), T ($20$)	YZ	Y ($25$), Z ($26$)	S and T are consecutive: $20 - 19 = 1$. Y and Z are consecutive: $26 - 25 = 1$. Offset S $\rightarrow$ Y: $25 - 19 = 6$. Offset T $\rightarrow$ Z: $26 - 20 = 6$. Commonality: Matches the pattern of options 1 and 2.
4. GH - OM	GH	G ($7$), H ($8$)	OM	O ($15$), M ($13$)	G and H are consecutive: $8 - 7 = 1$. O ($15$) and M ($13$) are not consecutive letters. Offset G $\rightarrow$ O: $15 - 7 = 8$. Offset H $\rightarrow$ M: $13 - 8 = 5$. Deviation: The second pair (OM) lacks consecutiveness. The offsets ($+8$, $+5$) are inconsistent and differ from the $+6$ pattern.

Odd One Out Determination Logic

Options 1, 2, and 3 exhibit a consistent structure:

Each pair consists of two consecutive letters from the alphabet.
The starting letter of the second pair is exactly 6 positions after the starting letter of the first pair.
Similarly, the second letter of the second pair is 6 positions after the second letter of the first pair.

Option 4 (GH - OM) breaks this pattern because the letters M and O in the second pair are not consecutive. Additionally, the numerical difference between the corresponding letters of the two pairs (G to O is 8, H to M is 5) is not a constant value of 6.

Reasoning Behind the Odd Cluster

Based on the analysis, the letter cluster pair GH - OM is the one that does not belong to the group established by the other three pairs. It fails to maintain the pattern of consecutive letters within the second pair and the consistent $+6$ positional shift.