If 390 is added in a number then number become `130%` of itself. Find the original number.

Options

A. `207`
B. `1300`
C. `702`
D. `1720`

Answer

To solve the problem step by step, we will denote the original number as \( K \).

### Step 1: Set up the equation
According to the problem, if we add 390 to the number \( K \), it becomes 130% of itself. We can express this mathematically as:
\[ K + 390 = 1.3K \]

### Step 2: Rearrange the equation
Next, we will rearrange the equation to isolate \( K \). Subtract \( K \) from both sides:
\[ 390 = 1.3K - K \]
This simplifies to:
\[ 390 = 0.3K \]

### Step 3: Solve for \( K \)
Now, we will solve for \( K \) by dividing both sides by 0.3:
\[ K = \frac{390}{0.3} \]

### Step 4: Calculate the value of \( K \)
To perform the division, we can multiply the numerator and denominator by 10 to eliminate the decimal:
\[ K = \frac{3900}{3} \]
Now, we can divide:
\[ K = 1300 \]

### Conclusion
Thus, the original number is \( K = 1300 \).

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