Which of the following numbers is a multiple of 6?

To determine if a number is a multiple of 6, we need to check if it satisfies two conditions:

• The number must be even (which means it is divisible by 2).
• The sum of its digits must be divisible by 3.

Let’s go through an example. Consider the following numbers: 12, 18, 20, and 30. We will check each one:

1. 12:
   • It is even (12 ÷ 2 = 6).
   • 1 + 2 = 3 (which is divisible by 3).

   Since both conditions are satisfied, 12 is a multiple of 6.

2. 18:
   • It is even (18 ÷ 2 = 9).
   • 1 + 8 = 9 (which is divisible by 3).

   Both conditions are satisfied, so 18 is also a multiple of 6.

3. 20:
   • It is even (20 ÷ 2 = 10).
   • 2 + 0 = 2 (which is not divisible by 3).

   Only the first condition is satisfied; hence, 20 is not a multiple of 6.

4. 30:
   • It is even (30 ÷ 2 = 15).
   • 3 + 0 = 3 (which is divisible by 3).

   Both conditions are satisfied, making 30 a multiple of 6.

So, from the given numbers, 12, 18, and 30 are multiples of 6, while 20 is not.

In conclusion, to find out if a number is a multiple of 6, just verify that it meets these two criteria:

• Is it even?
• Does the sum of its digits divide evenly by 3?

Using this method makes it easy to identify multiples of 6 quickly!