请教一道题about eco1104 谢谢

[Alucart]

a good has an income elasticity of demand of +0.5. a rise in income from 15,000 to 25,000 will lead to a "5 percent fall in quantity demanded of good"???? why?

希望eco的朋友能来帮帮忙

 

[popo]

我觉得应该是25percent fall in quantity demanded,不知道我这样做对不对？
%change in Income= change in income/average income=(25000-15000)/[(25000+15000)/2]=0.5
因为income elasticity 没有变，所以%change in quantity demand 和%change in Income 是成反比的，
所以qantity demanded要fall, =0.5*0.5=0.25

 

[Alucart]

同意 看来是答案错了

 

[安吉晓晓]

我也是这道题弄不清楚，应该是答案错了是不是？这道题是在去年的FINAL卷子里的吧，后面好象是25题左右还有一题很相似的，算来算去也是算不对，难道2道题的答案都错的？有人知道么？

 

[球迷鼠鼠]

我也做出来也和答案不对的. 因为income elasticity of demand of +0.5,所以这应该是 normal good吧,那么价格升, quantity demanded of good 好象也是升的,我做出来是"25% rise in the quantity of demanded " 也不知道对不对?

还有去年考试的18道也和答案不一样

 

[安吉晓晓]

and #18 has the same problem../the wrong answer