Based on the question, the ratio of the salt mixture is:
[tex]\frac{90grams}{1\text{liter}}[/tex]So, if we have 3.8 liters in 1 gallon, we would need 90grams x 3.8 = 342 grams of salt in 1 gallon.
[tex]\frac{90grams}{1\text{liter}}\times\frac{3.8liters}{1\text{gal}}=\frac{342grams\text{ }}{1gal}[/tex]The next step is to determine how many ounces are there in 342 grams. If 1 ounce = 28.35 grams, then 342 grams divide 28.35 grams = 12.06. Hence, in 342 grams, there are 12.06 ounces.
Thus, we can say that:
[tex]\frac{342\text{grams}}{1\text{gal}}=\frac{12.06\text{ounces}}{1\text{gal}}[/tex]The ratio of the salt mixture is 12.06 ounces per gallon.