關於最佳利率? - 經濟

手邊有一題考題:

Consider a bond market in which only consumers borrow and land.

Assume that all 200 consumers have the same two-period consumption-utility

function: U=0.5C1C2 . Let each of 160 consumers have the expected-income

stream y1=5000 y2=4000 and let each of the remaining 40 consumers have the

expected-income stream y1=4000 y2=8000. At what rate of interest rate will

the bond market be in equililbrium ?

我是用 MaxU=0.5C1C2

st: c1+c2/1+r=y1+y2/1+r

再加上兩種人各期的儲蓄加總為零算出來的

答案r=5/7 不知道有沒有錯 手邊沒答案 請知道的各位幫我看看 謝謝

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