The conversion rate is:
1 Gallon = 8 Pints
1 Pint = 16 Ounces
So if Katie drank 1 pint of the gallon of juice, there would be seven pints left for the baby. Since there's 16 ounces in a pint and there's seven pints then there would be 112 ounces left.
So your answer would be 7 Pints or 112 Ounces.
Hope this helped. Have a great day!