Brijesh Kumar

The phrase is: “A sharp rise in the prices of petrol” Here, petrol is indeed uncountable, but in common usage we often talk about “prices of petrol” because petrol is sold at different rates (e.g., normal, premium, or across different regions). So grammatically, “prices of petrol” is acceptable and widely used in economics/News-type contexts. If we write “price of petrol”, it implies a single uniform price everywhere. But since fuel rates vary, the plural “prices of petrol” is correct in this construction.