Let the cost price of the product be and the marked price be .
Step 1: Expressing the Cost Price and Marked Price - Since Gopi wants to make a 20% profit,
Step 2: Discounted Price for Ravi - Ravi receives a 10% discount.
Price paid by Ravi
We are told that Ravi saves Rs 15, which means the discount amount is Rs 15:
Discount
Thus, the marked price is:
Step 3: Calculate the Cost Price and Gopi's Profit From , we can solve for the cost price:
Now, Gopi sells the product to Ravi for , so the profit Gopi makes is:
Thus, the profit made by Gopi is Rs 10.