Answer :
Based on the information, the cost of one galon of milk is $3.79
Let us give a representation
Let the cost of a cereal box be $c and the cost of milk be $m
From the question, let us start with Simon
5 cereal boxes and 2 gallons of milk
That would be;
[tex]5c\text{ + 2g = 20.08 }\ldots.(i)[/tex]For Terri;
[tex]\begin{gathered} 3c\text{ + 3g = 18.87} \\ \text{divide through by 3} \\ c\text{ + g = 6.29} \\ c\text{ = 6.29-g }\ldots\ldots..(ii) \end{gathered}[/tex]We can proceed to substitute the second equation into the first
We have this as;
[tex]\begin{gathered} 5(6.29-g)\text{ + 2g = 20.08} \\ 31.45-5g+2g\text{ = 20.08} \\ 31.45-20.08\text{ = 5g-2g} \\ 3g\text{ = 11.37} \\ g\text{ = }\frac{11.37}{3} \\ g\text{ = 3.79} \end{gathered}[/tex]