The cost of Type 1 rice is Rs. 15 per kg and Type 2 rice is Rs. 20 per kg. If both Type 1 and Type 2 are mixed in the ratio of 2 : 3, then the price per kg of the mixed variety of rice is:
Answer: Option A
Let the price of the mixed variety be Rs. x per kg.
By rule of alligation, we have:
60 - 3x = 2x - 30
5x = 90
x = 18.