Why we are showing purchasers and cost of consumed materials, is it double the cost?

shivaji (job) (424 Points)

28 October 2019  
1.Cost of materials consumed.
2.Purchases of Stock-in-Trade.
3.Changes in inventories of finished

While preparing profit and loss statement under sechdule 3 why we are showing purchasers and cost of materials consumed ?
Is it double the cost?
I am unable to understand please explain