There are two types of milk. The price of one type of milk is ₹70/litre and the price of other type of milk is ₹50/litre. If the two types of milk are mixed, the price of new mixture will be ₹55/litre. Find the ratio of the two types of milk in this new mixture.

A

1 : 1

B

1 : 2

C

1 : 4

D

1 : 3