there are three kinds of salt water-----A,B and C.mix A with B by the proportion of 2:1,the mixture is 14% concentrated.if A ,B,and C are mixed by the proportion of 1:1:3 ,then the concentrated,how many grams of 70% concentration of
问题描述：
there are three kinds of salt water-----A,B and C.mix A with B by the proportion of 2:1,
the mixture is 14% concentrated.if A ,B,and C are mixed by the proportion of 1:1:3 ,then the concentrated,how many grams of 70% concentration of
答
有三种不同浓度的盐水A、B和C.将AB以2：1比例混合能得到浓度为14%的盐水.如果将ABC以1：1：3的比例混合,仍然要得到14%浓度的盐水的话需要浓度为70%的盐水C一共多少克?