The mixture consists of 2 parts of milk and 3 parts of syrup, so given a total of 5 equal parts of liquid.
Out of the total, the milk is 2 parts of 5 total, wich makes it: 2/5 of the drink.
The milk consists of 2/5 (two fifths) of the drink.
Relative to the parts of syrup, you need to answer:
2 milk per 3 syrup = 2:3 two to three of milk per syrup.
