Apply mathematical skills around cost structures and appropriate equations to answer the following, inclusive of all associated workings to maximise marks: Opening Inventory + Purchases - Closing Inventory Cost of Sales (COS) Mark up cost structure example with example of Margin cost structure Sales COS Gross Profit 125% (100%) 25% Sales COS Gross Profit 100% (75%) 25% a) A fire on 31st October destroyed some of a company's inventory and its inventory records. The following information is available: Inventory at 1st Oct Sales for Oct Purchases for Oct Inventory in good condition at 31st Oct The standard gross profit percentage on sales is 38%. Based on this information, what is the value of the inventory lost? Sales Revenue Purchases Gross Profit Selling Expenses Admin Cost Operating Loss 3,810,000 6,210,000 4,210,000 2,410,000 (3 marks) b) What are the definitions and business uses of calculating mark-up and margin? Please use Harvard when citing any sources. (4 marks) GBP 186,000 (182,000) 4000 (2000) (7200) (5200) c) Calculate mark-up (in percentage to 2 decimal places) (1 mark) d) Calculate the margin as a % 1 decimal places (1 mark) e) What is the operating profit margin percentage if the admin cost is reduced by 50%? Show this to 2 decimal place (2 marks) f) Define the following and provide respective examples with numeric calculations where possible. Please use academic sources: Trade discount (1 mark for definition and 1 for example) Simple interest (1 mark for definition and 1 for example) Compound interest (1 mark for definition and 1 for example)