Two brothers took the exam, the higher score is X and the lower one is Y. If the difference between the two scores is equal to their average, what is the value of Y/X ?  Choose one:
A) 3  B) 2.  C) 1/2.  D) 1/3.  E) There isn't enough data to answer the question
X-Y = (X+Y)/2   2 X - 2 Y = X + Y   X = 3 Y   Y/X = 1/3   1/3. is the answer.
<result>D</result>
Two brothers took the exam, the higher score is X and the lower one is Y. If the difference between the two scores is equal to their average, what is the value of Y/X ?