A diet contains 400 grams of a mixture of two foods, food X and food Y. Food X contains 10 percent protein and food Y contains 15 percent protein. If a diet provides exactly 46 grams of protein daily, how many grams of food X are in the mixture?  Choices
A) 280 B) 300 C) 320 D) 340 E) 360
Let x be the number of grams of food X in the mixture.   0.1x + 0.15(400-x) = 46   0.05x = 14   x = 280   The answer is 280.
<result>A</result>
A diet contains 400 grams of a mixture of two foods, food X and food Y. Food X contains 10 percent protein and food Y contains 15 percent protein. If a diet provides exactly 46 grams of protein daily, how many grams of food X are in the mixture?