This is my first example of linear programming with ratios and I'm not really sure what to do. I need help finding the constraints and then I can work the rest out myself.

Here's the question:

The owner of a factory that manufactures kitchen units has a contract to supply at least 72 units per week.

*He employs x artisans and y apprentices

*He cannot accommodate more than 16 employees.

*The Apprentices Act states that the ratio of apprentice to artisans is not greater than 9:2

*The Trade Union Act rules require that the ratio of apprentices to artisans is not smaller than 1:2.

*An artisan can produce 9 units per week while an apprentice can produce 6 units per week.

1. Write down a system of inequalities to represent the information above.

I can do the rest of the questions myself, just need to know the constraints.