Aunt Zhang bought back a batch of apples at a price of 0.8 yuan per kilogram. After selection, these apples were divided into two grades, A and B, with a quality ratio of 3:5. Grade B can only be sold at a price of 0.7 yuan. Aunt Zhang wants to To obtain 25% profit, how much should a first-class apple be sold at least per kilogram?
张阿姨以每千克0.8元的价格收购回一批苹果，经过挑选把这些苹果分成了甲、乙两个等级，质量比是3：5，乙等只能以0.7元价格出售，张阿姨要想获得25%的利润，甲等苹果每千克至少应卖多少元？
<result>1.5</result>