the contents of a certain box consist of 72 apples and 30 oranges . how many oranges must be added to the box so that exactly 30 % of the pieces of fruit in the box will be apples ?
"apple = ( apple + orange + x ) * 0.3 72 = ( 30 + 72 + x ) * 0.3 x = 138 answer : d"
subtract(add(72, 30), divide(72, divide(30, const_100)))