Find the selling price if the cost price is $360 and the gain is 12.5% on cost

It is important to note the details already given in the question. Based on those details the answer to the question can be easily determined. Now let us focus on the question given.

Cost price of the product in question = $360

Percentage of gain on the product = 12.5%

Then

amount of gain made on the product = (12.5/100) * 360 dollars

= 450/10 dollars

= 45 dollars

So

The selling price of the product in question = (360 + 45) dollars

= 405 dollars