Jean Jeanie spa. work 48 weeks a year to meet demand for jeans which is more or less constant at 200 units a week. They pay £20 for each pair of jeans and aim for a return of 20% on capital invested.

Annual storage costs are 5% of the value of goods stored. The purchasing department costs £65,000 a year and sends out an average of 2000 orders. Find the optimal order quantity for jeans, the best time between orders and the minimum cost of stocking the item.