So,it will be like each belt Rachel produces keeps her from producing 4 neckties, and each belt Mike produces keeps him from producing 1 necktie.
Rachel can make 12 neckties if she does nothing else and Mike can only 9.
Rachel has the advantage in the necktie department.
Mike can make 9 belts if he does nothing else, and Rachel can only manage 3.
Mike has the advantage in the belt department.
Hope this helps :)
Let me know if you need more help.
