推 bot:變動百分比的分母是"(Q1+Q2)/2" 你算式算出來應該是1/7不是7 02/27 19:43
→ bot:所以是 1/3.5 = 2/7 = 0.28 02/27 19:44
推 bot:老師剛交到彈性、不知道這樣對不對.... 02/27 19:46
→ goshfju:把P變化的百分比求出來 , 需求量的變動會大於那個幅度 02/29 05:01
推 askaaa:所以如果撇開計算不談 其實一秒可以選答案.. 03/02 19:26
來源: 93學年度技術學院專業科目(一) 管理類(二)管理類(四) 經濟學
科目:經濟學
問題:
假設某型電漿電視為正常財，消費者對其需求的弧彈性之絕對值大於1，當價格由每台20
萬元降為15萬元時，需求量會如何變動?
(A)增加，幅度小於14%
(B)減少，幅度大於28%
(C)增加，幅度大於28%
(D)減少，幅度小於14%
答案是:C
我的想法:令P1=200,000 P2=150,000 原本的需求量Q1 後來的需求量Q2
套入弧彈性的公式， ｜(Q2-Q1/Q2+Q1) 整個除以2｜
_____________________________ > 1
｜(P2-P1)/(P2+P1) 整個除以2｜
= = = = = = = = = = = = = = = = = = = = = = = = == ==
｜(Q2-Q1/Q2+Q1)｜ ｜(Q2-Q1/Q2+Q1)｜
____________________ = __________________ >1
｜-50,000/350,000｜ 1/7
= = = = = = = = = = = = = = = = = == === = = = = = = = = = = = = = =
｜(Q2-Q1/Q2+Q1)｜>7 所以 (Q2-Q1/Q2+Q1)>7 或 (Q2-Q1/Q2+Q1)<-7
= = = = = = = = = = = = = == = = = = = = = = = = = = = = = = = = = =
算出來Q2 >4/3 Q1 但怎麼會是大於28%呢？
高手可以幫我解惑嗎？謝謝。
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