數學難題(百分數)

oscar

這題是在我第一次數學Quiz遇到的難題...
(天：你也有不懂的數學題？)
這是關於百分數的~

問題：
There are 2 drinks.
Drink A contains 40% alcohol.
Drink B contains 65% alcohol.
In what ratio should we mix to make it become a drink of 50% alcohol?

我碰對了答案是3:2，但是不懂步驟，請各高手指點...

柳絮仙

There are 2 drinks.
Drink A contains 40% alcohol.
Drink B contains 65% alcohol.
In what ratio should we mix to make it become a drink of 50% alcohol?

0.0
too深哦中幾的maths???

幻藍

sahklr  在 2004-10-22 06:44 PM 發表:

0.0
too深哦中幾的maths???

中三掛

oscar

係呀...
都唔知點解個先生可以出到咁鬼難...

幻藍

oscar  在 2004-10-22 06:52 PM 發表:

係呀...
都唔知點解個先生可以出到咁鬼難...

上年個過同類的問題
好像是跟XX消元法有關的........

抹茶可樂

oscar  在 2004-10-22 06:31 PM 發表:

There are 2 drinks.
Drink A contains 40% alcohol.
Drink B contains 65% alcohol.
In what ratio should we mix to make it become a drink of 50% alcohol?

Let the ratio of Drink A and Drink B is m:n
Water contains in Drink A = 60%
Water contains in Drink B = 35%

40%m + 65%n = 60%m + 35%n
0.2m = 0.3n
m/n=3/2

The ratio of Drink A and Drink B is 3:2

就係咁啦喵∼'w'

[ Last edited by 落雷 on 2004-10-22 at 08:18 PM ]

oscar

落雷  在 2004-10-22 20:17 發表:

Let the ratio of Drink A and Drink B is m:n
Water contains in Drink A = 60%
Water contains in Drink B = 35%

40%m + 65%n = 60%m + 35%n
0.2m = 0.3n
m/n=3/2

The ratio of Drink A and Drink B  ...

...
咦...原來係咁容易ja...我仲諗到頭爆都未諗到...

rogergeot

佩服，佩服。落雷，你真捧。這條數學難題再一次證明我揀文科是正確。
因為我只是set到 40%m (alcohol)+ 65%n (alcohol) =50% (alcohol)

莫邪

天殺的
太久沒接觸過
不懂了=="

幻藍

what is "天殺的"???