茶葉A及茶葉B以x: y的比(以重量計)混合.A的原價為$80/kg,
B的原價為$100/kg.若A的價格增加10%,B的價格減少12%,
則混合後的茶葉每kg的價格不變. 求x:y
math 比
2008-08-02 2:26 am
回答 (1)
2008-08-02 2:31 am
✔ 最佳答案
原來價格=80(x/x+y)+100(y/x+y)=(80x+100y)/(x+y)後價格
=80(1+10%)(x/x+y)+100(1-12%)(y/x+y)
=(88x+88y)/(x+y)
即是說
(80x+100y)/(x+y)=(88x+88y)/(x+y)
80x+100y=88x+88y
12y=8x
x/y=12/8=6/4=3/2
x:y=3:2
收錄日期: 2021-04-23 22:31:02
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20080801000051KK02634