SSC CPO SI and ASI 2012 Paper

A man purchases milk for three consecutive years. In the first year, he purchases milk at rate of Rs. 7.50 per litre, in the second year, at the rate of Rs. 8.00 per litre and in the third year, at Rs. 8.50 per litre. If he purchases milk worth Rs. 4080 each year, the average price of milk per litre for the three years is