So there are 128 ounces in a gallon.
So half a gallon would have 64 ounces
Now it says Shari has 1 1/2 which means we would add 128 ounces and 64 ounces together to get 192 ounces.
1 1/2 gallons = 192 ounces
Now we take the 192 ounces and divide it into 12 because she has 12 friends to share with.
192/12 = 16 ounces
Each friend with get 16 ounces of orange juice.