Meiling has 1 1/4 liter of orange juice.
Express mixed fraction 1 1/4 into fraction :
So,
Meiling has 1 1/4 liter of orange juice = 5/4 liter juice
She drinks 1/3 liter
Amount of juice used = 1/3 liter
Left juice = Total amount of juice - Amount of juice drank by Meiling
Left juice = 5/4 - 1/3
Amount of juice left is 11/12 liter
Answer : 11/12 liter