Answer:
1/6
Step-by-step explanation:
Using Jenny's glass as the unit of volume, the total volume of syrup is apparently ...
1/3 + 2(1/12) = 6/12 = 1/2 . . . Jenny's glass
The total volume of chocolate milk is ...
1 + 2 = 3 . . . . . . . . . . . times Jenny's glass
Then the fraction of the total that is syrup is ...
(1/2)/(3) = 1/6 . . . . of the combined mix is syrup