Respuesta :
Let,
Number of Advance Tickets = a
Number of Same-Day tickets = s
Given,
Total 45 tickets sold
We can write
[tex]a+s=45[/tex]Also, each advance ticket cost $15 and same day tickets cost $20 for a total of $825. Thus, we can write:
[tex]15a+20s=825[/tex]We will multiply the first equation by - 15 and then add both equations. Then, solve for "s". The steps are shown below:
[tex]\begin{gathered} -15\times\lbrack a+s=45\rbrack \\ -15a-15s=-675 \\ ------------- \\ -15a-15s=-675 \\ 15a+20s=825 \\ ------------- \\ 5s=150 \\ s=\frac{150}{5} \\ s=30 \end{gathered}[/tex]Now, we can use this value of "s" and put it into Equation 1 and find the value of "a". Shown below:
[tex]\begin{gathered} a+s=45 \\ a+30=45 \\ a=45-30 \\ a=15 \end{gathered}[/tex]Answer