math
posted by ray .
Tickets to a show cost $10 for adults and $5 for children. The show was sold out, and the theatre has 500 seats. If the revenue collected from these ticket sales was $2900, how many adult tickets were sold?

Add up the money collected for each kind of ticket. Since 500 were sold, if there were x adult tickets, then there were 500x child tickets. So,
10x + 5(500x) = 2900