Question

Tickets to a play cost $8 each . Write an expression that gives the ticket cost in dollars for a group of girls and boys

Answer 1

If tickets cost $8 each, each tells me that I will need to multiply something. I don't know how many girls and boys this group will have the problem does not tell me, so I will just use the variable "x" to stand for that number. $8 times x will equal the total cost in dollars for the tickets.
So the expression would be  8x = total or just 8x.