The marked price of a watch is Rs. 800. A customer gets two successive discount on the marked price, the first being `10%`. What is the second discount if the customer pays Rs. 612 for it ?

Options

A. 14%
B. 15%
C. 17%
D. 18%

Answer

To solve the problem step by step, we need to determine the second discount given to the customer after the first discount of 10% on the marked price of Rs. 800. The customer ends up paying Rs. 612 for the watch.

### Step 1: Calculate the first discount
The first discount is 10% of the marked price.

\[ \text{First Discount} = \frac{10}{100} \times 800 = 80 \]

### Step 2: Calculate the price after the first discount
Now, we subtract the first discount from the marked price to find the price after the first discount.

\[ \text{Price after first discount} = 800 - 80 = 720 \]

### Step 3: Determine the amount paid by the customer
The customer pays Rs. 612 for the watch. We need to find the second discount based on the price after the first discount.

### Step 4: Calculate the second discount
To find the second discount, we subtract the amount paid by the customer from the price after the first discount.

\[ \text{Second Discount} = 720 - 612 = 108 \]

### Step 5: Calculate the second discount percentage
Now, we need to find the percentage of the second discount based on the price after the first discount.

\[ \text{Second Discount Percentage} = \left(\frac{108}{720}\right) \times 100 \]

Calculating this gives:

\[ \text{Second Discount Percentage} = \left(\frac{108}{720}\right) \times 100 = 15\% \]

### Final Answer
The second discount is **15%**.

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