In this number classification question, select the odd number from the given alternatives based on divisibility by 3.

Introduction / Context:
This quantitative aptitude question asks you to choose the odd number from four given options using basic divisibility rules. The key idea is to recognize a property that three numbers share and one does not. Here, divisibility by 3 is a very natural property to test because the numbers are small and their digit sums are easy to compute mentally.

Given Data / Assumptions:
- The numbers are 192, 240, 141, and 173.- All four numbers are positive integers.- We will focus on simple divisibility rules, especially divisibility by 3.

Concept / Approach:
The divisibility rule for 3 states that a number is divisible by 3 if the sum of its digits is a multiple of 3. This rule is quick to apply and avoids direct division. If three numbers pass this test and one fails, the failing number is the odd one out. We will apply this rule to each option in turn.

Step-by-Step Solution:
Step 1: For 192, the digit sum is 1 + 9 + 2 = 12. Twelve is a multiple of 3, so 192 is divisible by 3.Step 2: For 240, the digit sum is 2 + 4 + 0 = 6. Six is a multiple of 3, so 240 is divisible by 3.Step 3: For 141, the digit sum is 1 + 4 + 1 = 6. This is also a multiple of 3, so 141 is divisible by 3.Step 4: For 173, the digit sum is 1 + 7 + 3 = 11, which is not a multiple of 3. Therefore, 173 is not divisible by 3.Step 5: Three numbers are divisible by 3, while one is not.

Verification / Alternative check:
You can check directly by dividing each number by 3. 192 divided by 3 gives 64, 240 divided by 3 gives 80, and 141 divided by 3 gives 47, all whole numbers. However, 173 divided by 3 gives a non integer result. This direct calculation supports the digit sum test.

Why Other Options Are Wrong:
192: Multiple of 3, so it fits the main pattern.240: Also a multiple of 3 and belongs with 192 and 141.141: Again, divisible by 3 and not odd in this sense.

Common Pitfalls:
Candidates sometimes rely only on whether numbers are even or odd, but that is not the focus of this question. Here, both even and odd numbers can be divisible by 3, so you must apply the digit sum rule carefully.

Final Answer:
The odd number is 173 because it is not divisible by 3, unlike 192, 240, and 141 which are all multiples of 3.