If the sum of five consecutive numbers is `60` , then the first number is

Options

A. `8`
B. `10`
C. `12`
D. `15`

Answer

To solve the problem of finding the first number in a series of five consecutive numbers that sum to 60, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the problem**: We need to find five consecutive numbers whose sum is 60. Let's denote the first of these five consecutive numbers as \( x \).

2. **Express the consecutive numbers**: The five consecutive numbers can be expressed as:
- First number: \( x \)
- Second number: \( x + 1 \)
- Third number: \( x + 2 \)
- Fourth number: \( x + 3 \)
- Fifth number: \( x + 4 \)

3. **Set up the equation**: The sum of these five numbers can be written as:
\[ x + (x + 1) + (x + 2) + (x + 3) + (x + 4) = 60 \]

4. **Simplify the equation**: Combine like terms:
\[ 5x + (1 + 2 + 3 + 4) = 60 \]
\[ 5x + 10 = 60 \]

5. **Solve for \( x \)**: Subtract 10 from both sides:
\[ 5x = 60 - 10 \]
\[ 5x = 50 \]
Now, divide both sides by 5:
\[ x = \frac{50}{5} = 10 \]

6. **Conclusion**: The first number is \( x = 10 \).

### Final Answer:
The first number is **10**.