Find the sum of first 4 multiples of 9.

Options

A. 80
B. 90
C. 100
D. 105

Answer

To find the sum of the first 4 multiples of 9, we can follow these steps:

### Step 1: Identify the first 4 multiples of 9.
The multiples of a number can be found by multiplying that number by 1, 2, 3, and so on.

- First multiple: \( 9 \times 1 = 9 \)
- Second multiple: \( 9 \times 2 = 18 \)
- Third multiple: \( 9 \times 3 = 27 \)
- Fourth multiple: \( 9 \times 4 = 36 \)

### Step 2: List the multiples.
Now we have the first 4 multiples of 9:
1. 9
2. 18
3. 27
4. 36

### Step 3: Calculate the sum of these multiples.
Next, we add these multiples together:
\[ 9 + 18 + 27 + 36 \]

### Step 4: Perform the addition.
Now, let's add them step by step:
- First, add the first two multiples:
\[ 9 + 18 = 27 \]
- Next, add the third multiple:
\[ 27 + 27 = 54 \]
- Finally, add the fourth multiple:
\[ 54 + 36 = 90 \]

### Conclusion:
The sum of the first 4 multiples of 9 is **90**.

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