Directions: Find the odd man out: 10, 14, 16, 18, 21, 24, 26

### Concept & Even/Odd Numbers The sequence relies on the basic classification of integers into even and odd numbers. An even number is perfectly divisible by $2$. ### Step-by-Step Solution 1. Evaluate the sequence: $10, 14, 16, 18, 21, 24, 26$. 2. Note the parity (even/odd nature) of each term: - $10$ (Even) - $14$ (Even) - $16$ (Even) - $18$ (Even) - $24$ (Even) - $26$ (Even) 3. The number $21$ is not divisible by $2$, making it an odd number. 4. Hence, $21$ is the odd one out in a series of even numbers. ### Exam Strategy & Shortcut Scan the last digits of the numbers. If almost all end in $0, 2, 4, 6,$ or $8$, they are even. Any number ending in $1, 3, 5, 7,$ or $9$ immediately stands out. ### Common Pitfall Overthinking the sequence by looking for differences (which are $+4, +2, +2, +3, +3, +2$) and assuming a complex arithmetic progression instead of noticing the simple even/odd trait. ### Final Answer Therefore, the correct answer is **21**.