A rabbit on a controlled diet is fed daily 300 grams of a mixture of two foods, food X and food Y. Food X contains 10% protein and food Y contains 15% protein. If the rabbit's diet provides exactly 39 grams of protein daily, how many grams of food X are in the mixture.	Choices:
A) 120
B) 140
C) 150
D) 160
E) 200
Let x be the amount of food X.   0.1x + 0.15(300-x) = 39   0.05x = 6   x = 120   The answer is 120.
<result>A</result>
A rabbit on a controlled diet is fed daily 300 grams of a mixture of two foods, food X and food Y. Food X contains 10% protein and food Y contains 15% protein. If the rabbit's diet provides exactly 39 grams of protein daily, how many grams of food X are in the mixture.