In this number pair reasoning question, each option shows a pair in the form a–b: 63–36, 45–74, 48–84 and 26–62. Select the odd pair that does not follow the same pattern as the others.

Introduction / Context:
This is a classic odd one out question based on digit reversal. You are given four number pairs: 63–36, 45–74, 48–84 and 26–62. In three of these pairs, the second number is obtained by reversing the digits of the first number. One pair does not follow this rule and must be identified as the odd one out. Questions like this test your observation skills and familiarity with place value in two digit numbers.

Given Data / Assumptions:

• Pairs: 63–36, 45–74, 48–84 and 26–62.
• We focus on the relation between the tens digit and units digit of each number.
• In a valid pair, the second number should be the digit reversed form of the first number.
• Exactly one pair does not satisfy this reversal rule.

Concept / Approach:
A two digit number can be written as 10a + b, where a is the tens digit and b is the units digit. Reversing the digits gives the number 10b + a. For example, reversing 63 gives 36. We will check each pair to see whether b is indeed the reverse of a in this sense. The pair where the second number is not a simple reversal of the first is the odd one out.

Step-by-Step Solution:
Step 1: Check 63–36.First number = 63, tens digit 6 and units digit 3. Reversing gives 36, which matches the second number. So this pair follows the digit reversal rule.Step 2: Check 48–84.First number = 48, tens digit 4 and units digit 8. Reversing gives 84, which matches the second number. This pair also follows the rule.Step 3: Check 26–62.First number = 26, tens digit 2 and units digit 6. Reversing gives 62, which is exactly the second number. This pair is also correct.Step 4: Check 45–74.First number = 45, tens digit 4 and units digit 5. Reversing gives 54, but the second number is 74, not 54. Therefore this pair does not follow the reversal rule.Step 5: Identify the odd pair.45–74 is the only pair in which the second number is not a digit reversed form of the first number.

Verification / Alternative check:
A quick mental check is to write each first number and mentally swap its digits. If the resulting number matches the second member of the pair, the pair is consistent. For three pairs this works perfectly, but for 45–74 it fails because reversing 45 gives 54. This is a fast method you can use in actual exams to handle similar digit manipulation problems without any written work.

Why Other Options Are Wrong:
63–36: The second number is a perfect reversal of the first (63 reversed is 36).
48–84: The second number is again the reverse of the first (48 reversed is 84).
26–62: Follows the same rule (26 reversed is 62), so it is not the odd one out.

Common Pitfalls:
Some learners may overthink the relationships between the numbers, looking for addition, subtraction or multiplication patterns and overlooking the simple digit reversal. In many reasoning questions that display two digit numbers in pairs, always check for reversal or interchanging of digits before trying more complex operations. This habit saves time and avoids unnecessary confusion.

Final Answer:
The odd pair is 45–74, because in this pair the second number is not obtained by reversing the digits of the first number, unlike the other three pairs.