A chemist prepares 100 grams of medicine by mixing two ingredients X and Y. The rate of X is ₹1,500 per 100 grams and that of Y is ₹50 per 10 grams. X and Y are mixed in such a way that the cost of the resulting medicine is ₹13 per gram. What is the quantity of X (in grams) in the medicine?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e 80.
X: ₹1500 per 100 g ⇒ ₹15 per g
Y: ₹50 per 10 g ⇒ ₹5 per g
Assume X = x g, Y = (100 − x) g
Since the total mixture is 100 g.
Total cost = 15x + 5(100 − x) = 15x + 500 − 5x = 10x + 500
Given cost per gram of mixture = ₹13
So total cost = 100 × 13 = ₹1300
hence total cost = 10x + 500 = 1300
⇒ 10x = 800 ⇒ x = 80
Quantity of X = 80 grams