Understanding the Letter Analogy: CD : HI

The question asks us to find a pair of letters that has the same relationship as the given pair, CD : HI. This type of question is known as a letter analogy. To solve it, we first need to understand the pattern or relationship between CD and HI.

Let's look at the position of these letters in the English alphabet:

• C is the 3rd letter.
• D is the 4th letter.
• H is the 8th letter.
• I is the 9th letter.

The first pair is CD, which are consecutive letters. The second pair is HI, which are also consecutive letters.

Now let's see the distance between the letters of the first pair and the corresponding letters of the second pair:

• From C to H: C → D → E → F → G → H. Counting positions, H is 5 positions after C ($8 - 3 = 5$).
• From D to I: D → E → F → G → H → I. Counting positions, I is 5 positions after D ($9 - 4 = 5$).

So, the pattern is that the second pair starts 5 positions after the first letter of the first pair and ends 5 positions after the second letter of the first pair.

Another way to look at it is the letters between the first pair and the second pair. CD are consecutive. HI are consecutive. The letters between D and H are E, F, G. There are 3 letters between the end of the first pair (D) and the start of the second pair (H).

Analyzing the Options for Analogous Pair

Now let's examine each option to see which one follows the same pattern.

Option 1: PQ : UV

• P is the 16th letter. Q is the 17th letter. (Consecutive)
• U is the 21st letter. V is the 22nd letter. (Consecutive)
• From P to U: U is 5 positions after P ($21 - 16 = 5$).
• From Q to V: V is 5 positions after Q ($22 - 17 = 5$).

Alternatively, the letters between Q and U are R, S, T. There are 3 letters between Q and U.

This option follows the pattern of adding 5 positions to each letter, or having 3 letters between the end of the first pair and the start of the second pair.

Option 2: IJ : MN

• I is the 9th letter. J is the 10th letter. (Consecutive)
• M is the 13th letter. N is the 14th letter. (Consecutive)
• From I to M: M is 4 positions after I ($13 - 9 = 4$).
• From J to N: N is 4 positions after J ($14 - 10 = 4$).

This option involves adding 4 positions, not 5. The letters between J and M are K, L (2 letters), not 3.

This option does not follow the pattern.

Option 3: KL : NO

• K is the 11th letter. L is the 12th letter. (Consecutive)
• N is the 14th letter. O is the 15th letter. (Consecutive)
• From K to N: N is 3 positions after K ($14 - 11 = 3$).
• From L to O: O is 3 positions after L ($15 - 12 = 3$).

This option involves adding 3 positions, not 5. The letter between L and N is M (1 letter), not 3.

This option does not follow the pattern.

Option 4: AB : XY

• A is the 1st letter. B is the 2nd letter. (Consecutive)
• X is the 24th letter. Y is the 25th letter. (Consecutive)
• From A to X: X is 23 positions after A ($24 - 1 = 23$).
• From B to Y: Y is 23 positions after B ($25 - 2 = 23$).

This option involves adding 23 positions, not 5.

This option does not follow the pattern.

Conclusion

Based on our analysis, only Option 1 (PQ : UV) exhibits the same relationship as the given pair (CD : HI). The relationship is that both letters in the second pair are 5 positions ahead of the corresponding letters in the first pair, or there are 3 letters between the end of the first pair and the start of the second pair.

Revision Table: Comparing Pairs

Additional Information on Letter Analogies

Letter analogies are common in reasoning tests. They assess your ability to identify patterns in sequences of letters. The patterns can be based on:

• Position in the alphabet (like in this question)
• Skipping letters
• Reverse alphabetical order
• Vowels or consonants
• Combinations of these rules

Practicing with different types of letter series and analogies helps you quickly identify the underlying pattern during an exam.