Answer :
Given
$6.00 adults
$2.50 Kids
Total $39.00
2 fewer adults than kids
Procedure
a = adults
k = kids
[tex]\begin{gathered} 6a+2.5k=39 \\ a=k-2 \end{gathered}[/tex]solving
[tex]\begin{gathered} 6(k-2)+2.5k=39 \\ 6k-12+2.5k=39 \\ 8.5k=39+12 \\ k=\frac{51}{8.5} \\ k=6.0 \end{gathered}[/tex]Now for adults
[tex]\begin{gathered} a=k-2 \\ a=6-2 \\ a=4 \end{gathered}[/tex]Answer=
6 kids
4 adults