1.雞場面積為150m2 一邊靠墻(長為18m) 雞場另外三邊用竹籮巴圍成
全長35m 求雞場的長與寬各多小?
我唔識點去搵條方程出黎 有沒人可以教教我?
2.一種藥品經2次降價,由每盒60元調到52元 平均每次降價的百分率是多少?
依條我唔知應該點做 識的教埋我 thx!!
代數問題 我唔識點計(中三) 急!!
2008-10-21 7:20 am
回答 (1)
2008-10-21 7:41 am
✔ 最佳答案
1. Assume 雞場長為 L 雞場寬為WL * W = 150
=> L = 150/W
L + 2 W = 35
=> 150/W + 2W = 35
=> 150 + 2W^2 = 35W
=> 2W^2 -35W +150 = 0
=> W = 10 OR 7.5
L = 15 OR 20 but 墻(長為18m),所以L只可長15m,W只可是10m。
2. Assume the rate is x
60 * (1-x)^2 = 52
1-2x+x^2 = 52/60
x^2 - 2x +1-52/60 =0
x =1.93 or 0.069
x must less than 1 so the only answer is 0.069 or 6.9%
參考: CLOUDWAH - 獻醜
收錄日期: 2021-04-23 18:08:11
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20081020000051KK02320