The sum of a number and seven times of it is equal to the product of 25.6 and 12.5. what will be one fourth of that number?

Options

A. 16
B. 12
C. 8
D. 10

Answer

To solve the problem step by step, let's break it down:

### Step 1: Define the variable
Let the unknown number be represented by \( x \).

### Step 2: Set up the equation
According to the problem, the sum of the number and seven times the number is equal to the product of 25.6 and 12.5. This can be expressed mathematically as:
\[ x + 7x = 25.6 \times 12.5 \]

### Step 3: Simplify the left side of the equation
Combine like terms on the left side:
\[ 8x = 25.6 \times 12.5 \]

### Step 4: Calculate the product on the right side
Now, calculate \( 25.6 \times 12.5 \):
\[ 25.6 \times 12.5 = 320 \]
So, the equation now is:
\[ 8x = 320 \]

### Step 5: Solve for \( x \)
To find \( x \), divide both sides of the equation by 8:
\[ x = \frac{320}{8} = 40 \]

### Step 6: Find one fourth of the number
Now, we need to find one fourth of \( x \):
\[ \frac{x}{4} = \frac{40}{4} = 10 \]

### Final Answer
Thus, one fourth of that number is \( 10 \).

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