SAT Question 1ce51655: Linear Equations In One Variable answer and explanation with Desmos solution

Choice D is correct. It's given that the bowl starts with $20$ ounces of water and has $9$ ounces of water remaining after a period of time has passed. The amount of water the bowl has lost during the time period can be found by subtracting the remaining amount of water from the amount of water the bowl starts with, which yields $20-9$ ounces, or $11$ ounces. This means the bowl loses $11$ ounces of water during that period of time. It's given that the amount of water decreases by $1$ ounce every $4$ days. Letting $t$ represent the number of days the bowl has been uncovered, it follows that $\frac{1}{4}=\frac{11}{t}$. Multiplying both sides of this equation by $4t$ yields $t=44$. Therefore, the bowl has been uncovered for $44$ days.