sat suite question viewer
A mixture consisting of only vitamin D and calcium has a total mass of grams. The mass of vitamin D in the mixture is grams. What is the mass, in grams, of calcium in the mixture?
Explanation
Choice C is correct. Let represent the mass, in grams, of vitamin D in the mixture, and let represent the mass, in grams, of calcium in the mixture. It’s given that the mixture consists of only vitamin D and calcium and that the total mass of the mixture is grams. Therefore, the equation represents this situation. It’s also given that the mass of vitamin D in the mixture is grams. Substituting for in the equation yields . Subtracting from both sides of this equation yields . Therefore, the mass of calcium in the mixture is grams.
Choice A is incorrect and may result from conceptual or calculation errors.
Choice B is incorrect. This is the total mass, in grams, of the mixture, not the mass, in grams, of calcium in the mixture.
Choice D is incorrect. This is the mass, in grams, of vitamin D in the mixture, not the mass, in grams, of calcium in the mixture.