經濟租相關問題 - 經濟

小弟今年修了學校開的經濟學概論

最近提到經濟租和要素雇用的觀念

課本中有一個例題是這樣問的。

「Three machines are employed in an isolated area. They each produce 2000 units

of output per month, the first requiring $20000 in raw materials, the second

$25000, and the third $28000. What would you expect to be the monthly charge

for the first and second machines if the services of the third machine can be

hired at a price of $9000 per month? Which parts of the charges for the first

two machines are economic rent?」

跟同學討論了以後也沒有結果，都不太懂題目的意思

也不太了解要從哪個觀念下手

我的想法是得到相同的產出，那投入應該要相等

可是又覺得怪怪的

不知道有沒有版友能為我解惑一下，謝謝

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