Find the odd number: Among 18, 30, 26, and 24, three are multiples of 6 while one is not. Identify the non-multiple of 6.

Introduction / Context:
The majority are divisible by 6 (i.e., by both 2 and 3). The outlier fails divisibility by 3.

Given Data / Assumptions:

• Options: 18, 30, 26, 24.
• Multiple of 6 ⇔ divisible by 2 and by 3.

Concept / Approach:
Apply digit-sum test for 3 and check evenness.

Step-by-Step Solution:

Verification / Alternative check:
Direct division shows only 26/6 is non-integer.

Why Other Options Are Wrong:
They satisfy divisibility by both 2 and 3.

Common Pitfalls:
Equating evenness with being a multiple of 6; the 3-test is also required.

Final Answer:
26 is the odd number.