First, we should convert all of the measurements into one unit.
Let's convert everything into fluid ounces since it's the smallest unit in the American Liquid Measurement system.
They had 6 1/2 quarts of skim milk.
6 1/2 quarts=208 fluid ounces.
They had 1 pint of whole milk, which is equal to 16 fluid ounces.
Next, we add both numbers 208, and 16, together.
208+16=224.
So far Ice-Cream Palace has 224 fluid ounces of milk.
Next, we'll convert 6 gallons into fluid ounces.
6 gallons=768 fluid ounces.
Next, we subtract 224 from 768.
768-224=544.
That means they need to buy 544 ounces of milk.
All we have to do now is convert 544 into pints.
544 ounces= 34 pints.
They still need to buy 34 pints of milk.
I hope you have a wonderful day! :D