The contents of a certain box consist of 20 apples and 30 oranges. How many oranges must be added to the box so that exactly 20% of the pieces of fruit in the box will be apples?  Choose the correct option.
A) 50
B) 55
C) 75
D) 85
E) 100
apple = (apple + orange + x)*0.2   20 = (30 + 20 + x)*0.2   x = 50   50nswer: 50
<result>A</result>
The contents of a certain box consist of 20 apples and 30 oranges. How many oranges must be added to the box so that exactly 20% of the pieces of fruit in the box will be apples?