The cost of type - I rice is Rs. 15 per kg and type - II is Rs. 20 per kg. If both type - I and type - II are mixed in the ratio of 2 : 3, then find the price per kg of the mixed variety.
Correct Answer: 18
Explanation:
Let the price per kg of mixed variety be Rs. P;
then By the rule of alligation,
Now, (20 - P) / (P - 15) = (2 / 3)
⇒ 60 – 3P = 2P – 30
⇒ 5P = 90
∴ P = Rs. 18
