Write the following sets in roster form and also in set builder form :
{whole numbers divisible by 4 and less than 30}

Answer

To solve the question of writing the set of whole numbers divisible by 4 and less than 30 in both roster form and set builder form, we can follow these steps:

### Step 1: Identify the whole numbers divisible by 4
Whole numbers divisible by 4 are numbers like 0, 4, 8, 12, 16, 20, 24, 28, etc.

### Step 2: List the whole numbers divisible by 4 that are less than 30
We need to find all the whole numbers that are divisible by 4 and also less than 30. The numbers are:
- 0 (divisible by 4)
- 4 (divisible by 4)
- 8 (divisible by 4)
- 12 (divisible by 4)
- 16 (divisible by 4)
- 20 (divisible by 4)
- 24 (divisible by 4)
- 28 (divisible by 4)

### Step 3: Write the roster form
The roster form lists all the elements of the set. Therefore, the roster form of the set is:
\[ \{0, 4, 8, 12, 16, 20, 24, 28\} \]

### Step 4: Write the set builder form
The set builder form describes the properties of the elements in the set. For this set, we can express it as:
\[ \{ x \mid x \text{ is a whole number, } x \text{ is divisible by } 4, \text{ and } x < 30 \} \]

### Final Answer
- Roster Form: \{0, 4, 8, 12, 16, 20, 24, 28\}
- Set Builder Form: \{ x \mid x \text{ is a whole number, } x \text{ is divisible by } 4, \text{ and } x < 30 \}