A farmer has enough food to feed her 1000 cows for 50 days. After 10 days some of the cows run away and the food was now enough for the same period of 50 days as before. How many cows ran away?	Answers:
A) 300	B) 200	C) 500	D) 400	E) 250
1000 ---- 50   1000 ---- 40   x ---- 50   x*50 = 1000*40   x = 800   1000   -------   200   Answer = 200
<result>B</result>
A farmer has enough food to feed her 1000 cows for 50 days. After 10 days some of the cows run away and the food was now enough for the same period of 50 days as before. How many cows ran away?