A measuring cup contains 1/5 of a cup of orange juice.It is then filled to the 1 cup mark with a mixture that contains e
问题描述：
A measuring cup contains 1/5 of a cup of orange juice.It is then filled to the 1 cup mark with a mixture that contains equal amounts of orange,grapefruit,and pineapple juices.What fraction of the final mixture is orange juice?
答
The mixture is 1 - 1/5 = 4/5 of the cup,containing equal amounts of orange,grapefruit,and pineapple juices,so in this part,each juice is (4/5)*(1/3) = 4/15 of the cup; orange juice is 4/15 + 1/5 = 7/1...