I have some difficulties with following problem (I need the solution urgently for tomorrow): Production levels for Giles Fashion vary greatly according to consumer acceptance of the latest styles. Therefore, the company's weekly orders of wool cloth are difficult to predict in advance. On the basis of 5 years data, the following probability distribution for the company's weekly demand for wool has been computed: Amount of wool (lb) Probability 2500 0.30 3500 0.45 4500 0.20 5500 0.05 >From these data, the raw-materials purchaser computed the expected number of pounds required. Recently, she noticed that the company's sales were lower in the last year than in years before. Extrapolating, she observed that the company will be lucky if its weekly demand averages 2,500 this year. (a) What was the expected weekly demand for wool based on the distribution from past data? (b) If each pound of wool generates $5 in revenue and costs $4 to purchase, ship, and handle, how much would Giles Fashion stand to gain or lose each week if it orders wool based on the past expected value and company's demand is only 2,500? (End of the text of the problem.) Possible solution (in my opinion): I. (a) I fink is obvious: If X means company's weekly demand for wool (lb), then the expected weekly demand for wool based on the distribution from past data =E(X) = 0.3*2500+0.45*3500+0.20*4500+0.05*5500= = 3500. Am I right? (b) Actually I am not sure what company's weekly demand for wool in the past data (table of probability distr.) means. It is the amount of wool which company bought weekly or is the amount of wool which company sold (in it's products) weekly? The last sentence make difference between company's orders (it orders wool based...) and company's demand ( and company's demand is only 2,500) (I think but I am not sure, it's actually company's weekly demand for wool). So In my opinion company's weekly demand for wool means: the amount of wool which company sold (in it's products) weekly? Am I right? I am not sure what the last sentence means. Does it mean that the company orders weekly 3500 lb of wool ( it orders wool based on the past expected value and the past expected value = 3500 from (a)) and it sells weekly 2500 lb in their products (and company's demand is only 2,500)? If so the solution seems to be: The company should expect to gain weekly: 2500*1$-1000*4$=-1500$ so in fact it should expect to lose weekly 1500$. -- Am I right? Maybe I should consider that the company's weekly demand is 2500 lb but it orders are: Amount of wool (lb) Probability 2500 0.30 3500 0.45 4500 0.20 5500 0.05 (Loss | Orders=2500 ) 0$ -1500$ ... probability 0.30 0.45 E(Loss | Orders=2500 ) = 0*0.3+(-1500)*0.45+ ... Please somebody correct me if I am wrong. Jan ================================================================= Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =================================================================