If an article is sold for ₹x, thee is a loss of 15%. If the same article is sold for ₹y, there is a profit of 15%. The ratio (y-x) : (y+x) is

3 : 20

Let the cost price of the article = 100

SP when sold at 15% loss = 85 = x

SP when sold at 15% profit = 115 = y

Now according to the question,

(y-x) : (y+x)

= 115 - 85 : 115 + 85

= 30 : 200

= 3 : 20