The contents of a certain box consist of 40 apples and 30 oranges. How many oranges must be added to the box so that exactly 40% of the pieces of fruit in the box will be apples?  Choose the correct choice from the following:
A) 40
B) 50
C) 60
D) 70
E) 30
apple = (apple + orange + x)*0.4   40 = (30 + 40 + x)*0.4   x = 30   Answer: 30
<result>E</result>
The contents of a certain box consist of 40 apples and 30 oranges. How many oranges must be added to the box so that exactly 40% of the pieces of fruit in the box will be apples?