有限資源下最佳資源組合 - 會計

M.Company produces three products,X,Y and Z.Data concerning the three products
follows(per unit)

X Y Z
───── ───── ─────
Selling Price $ 60 $ 30 $ 50
Variable expenses
Direct meterials $ 20 $ 10 $ 6
Other variable expenses 12 32 15 25 29 35
── ── ── ── ── ──
Contribution margin $28 $ 5 $15
══ ══ ══
Estimatrd monthly demand(units) 400 500 300

The same material is used in each product.The material costs $4 per pound with
a maximum of 3,000 pounds available each month.The company's present employees
and equipment can produce all three products.
1.Indicate how much of each product should be made each month so that the
company can maximum its profit.
2.What is the highest price, in term of per pound,that M.company would be
willing to pay for additional material?

答案:1. X Y Z
單位邊際貢獻 $28 $5 $15
每單位所需材料(磅) 5 2.5 1.5
每磅貢獻 5.6 2 10

所以生產優先順序: Z(300單位)>X(400單位)>Y(220單位)

2.設每磅價為P
則 $30-2.5xP-15=0
P=$6

我的問題是...為啥解答1.最後的Y是220單位!?
2.為什麼要從Y而不是從X.Z去設P來作答!?

請各位高手幫我解解答吧~~~拜託了感恩!!!

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