[tiếng anh 1] [Ở rể] [toã¡n há» c kỳ 1] [ngæ°á» i bã¡n mã¬nh] [Cao C] [Con �] [54 năm] [干部人事档案编号在线查询] [This year, Henry will save a certain amount of his income, and he will spend the rest. Next year, Henry will have no income, but for each dollar that he saves this year, he will have 1 r dollars available to spend. In terms of r, what fraction of his income should Henry save this year so that next] [sã¡ch cá»§a ewar thá» p]