Solution
Miguel and 3 of his friends went to the movies.
They originally had a total of $40.00.
Since each boy have the same amount, let the amount each boy have left after the ticket be m
The amount each boy have left is
[tex]4\times m=4m[/tex]Each boy spent $7.50 on a ticket, i.e
[tex]4\times7.5[/tex]The amount of money that each boy have left can be expressed as
[tex]\begin{gathered} 4m+4(7.5)=40 \\ 4(m+7.5)=40 \end{gathered}[/tex]Solving for m
[tex]\begin{gathered} 4(m+7.5)=40 \\ \text{Divide both sides by 4} \\ \frac{4(m+7.5)}{4}=\frac{40}{4} \\ m+7.5=10 \\ \text{Collect like terms} \\ m=10-7.5 \\ m=\text{ \$2.5} \end{gathered}[/tex]Hence, each boy have $2.5 left after buying his ticket.