Rashmi's weight decreased by `8%` over three months. If the weight lost was 4.2 kg, what was her weight 3 months ago?

Answer

To find Rashmi's weight 3 months ago, we can follow these steps:

### Step 1: Define the variables
Let \( x \) be Rashmi's weight 3 months ago.

### Step 2: Set up the equation
Since Rashmi's weight decreased by 8%, we can express this decrease mathematically. The weight lost is given as 4.2 kg, which represents 8% of her original weight \( x \).

So, we can write the equation:
\[ 0.08x = 4.2 \]

### Step 3: Solve for \( x \)
To find \( x \), we need to isolate it. We can do this by dividing both sides of the equation by 0.08:
\[ x = \frac{4.2}{0.08} \]

### Step 4: Calculate the value
Now, we can calculate \( x \):
\[ x = \frac{4.2}{0.08} = \frac{4.2 \times 100}{8} = \frac{420}{8} \]

Now, performing the division:
\[ 420 \div 8 = 52.5 \]

### Step 5: Conclusion
Thus, Rashmi's weight 3 months ago was:
\[ \boxed{52.5 \text{ kg}} \]

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