Respuesta :
a) We have to write a system of equations to solve this problem.
The variables are the price of the adult ticket (A) and the price of the student ticket (S).
On the first day the sales where $139, which correspond to 6 adult tickets and 11 students tickets.
The total sales are equal to the sum of the sales of the adult tickets (price times number of tickets) and the sum of the sales of the students tickets (price times number of tickets).
We then can write:
[tex]6\cdot A+11\cdot S=139[/tex]We can use the same logic for the second day and obtain:
[tex]12\cdot A+2\cdot S=178[/tex]Then, we have a system of equations as:
[tex]\begin{cases}6A+11S={139} \\ 12A+2S={178}\end{cases}[/tex]b) We can find the prices by solving this system of equations.
We can use elimination, by substracting two times the first equation from the second equation:
[tex]\begin{gathered} 12A+2S-2(6A+11S)=178-2(139) \\ 12A+2S-12A-22S=178-278 \\ -20S=-100 \\ S=\frac{-100}{-20} \\ S=5 \end{gathered}[/tex]We can now use this information to find A as:
[tex]\begin{gathered} 6A+11S=139 \\ 6A+11(5)=139 \\ 6A+55=139 \\ 6A=139-55 \\ 6A=84 \\ A=\frac{84}{6} \\ A=14 \end{gathered}[/tex]Then, the price for an adult ticket is $14 and the price for a student ticket is $5.
c) He sells 9 student tickets and 3 adult tickets for the 3rd day, so we can calculate how much money this represents as:
[tex]\begin{gathered} 9S+3A \\ 9(5)+3(14) \\ 45+42 \\ 87 \end{gathered}[/tex]The total revenue is $87.
Now, if we calculate the budget as the sum of the revenue for the 3 days:
[tex]\begin{gathered} B=R_1+R_2+R_3 \\ B=139+178+87 \\ B=404 \end{gathered}[/tex]Answer:
a) The equations are:
6A + 11S = 139
12A + 2S = 178
where A: price of adult ticket, S: price of student ticket.
b) A = 14, S = 5
c) The budget has to be $404, the revenue of the three days.