A person bought 60 quintals of rice of two different sorts for Rs. 4642·50. The better sort costs Rs. 80 per quintal and the worse Rs. 75·50 per quintal. How many quintals were there of each sort?

• 25 quintals, 35 quintals
• 20 quintals, 40 quintals
• 32 quintals, 28 quintals
• None of these