數學問題~~10分!!!
2007-11-04 12:13 am
how many gram of water must be added to 48g of alcohol to make a solution which has 25% alcohol?
回答 (2)
2007-11-05 1:03 am
✔ 最佳答案
其實點解唔可以用方程呢？方程係最好的方法，不過唔用都得ge(麻煩D)!第一題：
48-(48×25%)÷25%
=36÷25%
=144
第二題答左你lu...^^copy一次
$30×(1+20%)÷(1-10%)
=$36÷0.9
=$40
參考: 自己
2007-11-04 12:24 am
Let x gram be the weight of water to be added.
48g / (48g + x g) = 25%
48/(48+x) = 0.25
48 = 12 + 0.25x
36 = 0.25x
x = 144
Therefore, 144 grams of water must be added.
48g / (48g + x g) = 25%
48/(48+x) = 0.25
48 = 12 + 0.25x
36 = 0.25x
x = 144
Therefore, 144 grams of water must be added.
收錄日期: 2021-04-13 14:19:16
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20071103000051KK02598