请教一道 prep 题

lbling417 · 发表于 2013-9-18 10:30:53

the rate of a certain chemical reaction is directly proportional to the square of the concentration of chemical A present and inversely propotional to the cncentratiion of chemical B present. If the concentration of chemical B is increased by 100 percent, which of the following is closet t othe percent change in the concentration of chemical A required to keep the reaction rate unchanged?
答案是 40%

疑惑中。。

csd9235 · 发表于 2013-9-18 11:19:36

同问同问

cherriben · 发表于 2013-9-18 11:27:36

1.4x1.4=1.96 close to 2

csd9235 · 发表于 2013-9-18 11:27:38

我算出来得41.4%，设x=a^2／b因为x为那个reaction和a^2正比b反比，这时要使得x不变，b增加百分之百，问a增加百分之几。使得x=[a（1+y%）]^2／b（1+1）让x相等可以解出y为41.1%

lbling417 · 发表于 2013-9-18 17:32:35

非常感谢。。。。

请教一道 prep 题

所属分类: GMAT考试

正在浏览此版块的会员 ()

浏览过的版块