1. The problem asks to circle all multiples of 6. 2. A multiple of 6 is any number that can be expressed as $6 \times n$ where $n$ is an integer. 3. Important rule: Multiples of 6 include numbers like 6, 12, 18, 24, 30, and so on. 4. To identify multiples of 6, check if the number is divisible by 6 without remainder. 5. For example, 12 is a multiple of 6 because $12 = 6 \times 2$. 6. Similarly, 18 is a multiple of 6 because $18 = 6 \times 3$. 7. Circle all such numbers in the given list that satisfy this condition.