最佳答案:2/5,设男生总数x,女生总数,y,有(x+y)*3/10=x/3+y/4,得x=3*y/2,所以女生占总数为,y/(x+y)=2/5
最佳答案:the boy with glasses doesnt know that i like him
最佳答案:设男有x,女有y则男戴眼镜的有1/4x,没戴的有3/4x女戴眼镜的有1/3y,没戴的有2/3y所以总戴眼镜的有1/4x+1/3y,没戴的有3/4x+2/3y即: