Need someone help, about math20a?

question:
your company has been chosen by Tim Horton's Children Summer Camps to select a t- shirt company that will provide the best price for the t- shirt that they give to each child at the end of camp. The board of director's has narrowed the decision down to two companies. Billboard t - shirt printing charges $1163 for a logo design with three colors, and an additional $8.75 per t -shirt. T - print charges $375.50 for a logo design with three colors, and an additional $11.25 per t- shirt.


How set up the system of equation, including the 'let' statements to find the number?
I got the wrong answer for my project..
like: 8.75x+y =1163
11.25x+y = 375.50