Answer:
[tex]20[/tex] tickets at [tex]\$5.50[/tex] and [tex]10[/tex] tickets at [tex]\$7.50[/tex].
Step-by-step explanation:
Assume that [tex]x[/tex] of the tickets were sold at [tex]\$5.50[/tex]. The other [tex](30 - x)[/tex] tickets would be sold at [tex]\$7.50[/tex].
The total ticket sale revenue would be: [tex]5.50\, x + 7.50\, (30 - x)[/tex].
It is given that the total ticket sale revenue is [tex]\$185[/tex]. In other words:
[tex]5.50\, x + 7.50\, (30 - x) = 185[/tex].
Rearrange and solve this equation for [tex]x[/tex]:
[tex](5.50 - 7.50)\, x = 185 - (7.50)\, (30)[/tex].
[tex]\begin{aligned}x &= \frac{185 - (7.50)\, (30)}{5.50 - 7.50} \\ &= 20\end{aligned}[/tex].
In other words, [tex]20[/tex] of the tickets were sold at [tex]\$5.50[/tex]. The other [tex](30 - 20) = 10[/tex] tickets were sold at [tex]\$7.50[/tex].