Answer: 19.81 gallons
Step-by-step explanation:
Given : A dialysis unit requires 75000 mL of distilled water.
We know that 1 gallon= 4 quarts
and 1 quart= 946.353 ml
Then, 1 gallon = [tex]4\times946.353=3785.412[/tex] milliliter.
Using Unitary method ,
[tex]\text{1 milliliter = }\dfrac{1}{3785.412}\text{ gallon}[/tex]
Then, [tex]\text{75000 milliliters = }\dfrac{75000}{3785.412}\text{ gallon}[/tex]
[tex]=19.8129132643\approx19.81\text{ gallons}[/tex]
Hence, 19.81 gallons water is needed.