NDPfc__?
Subsidy__40
Sales__800
Export__ 100
Closing stock__20
Opening stock__50
Intermediate purchases__ 500
Purchases of machinery of own use __ 200
Depreciation__ 30
Import of raw material__ 60

Dear student
Ans 2.
We do not add exports separately when sales are given as exports are treated as a part of total sales. Similarly, import of raw materials is not included in the value-added method, since they are already a part of the intermediate cost.
So, Net Value added at factor cost = Sales + Change in Stock - Intermediate Purchases - Depreciation - Net Indirect Taxes
                                                       = Sales + (Closing Stock - Opening Stock) - Intermediate Purchases - Depreciation - (Indirect taxes - Subsidies)
                                                        = 800 + 20 - 50 - 500 - 30 - (0 - 40)
                                                       = 280

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