Valuation of closing stock

Shubham Jain (Haryana) (131 Points)

26 January 2015  
I see in one question that closing stock as per financial account is (direct mat.+wages+factory OH)/(total unit)*unit closing stock whereas as per cost book profit is ( direct mat.+wages + factory OH + office OH)/(total unit produced)* units in closing stock what is the reason behind it can someone tell me