If you understand your solution deeply, you will be able to modify it and apply it in a new situation. For the Extend stage of modeling, pose a new, related and more complex question and answer it mathematically. If you do not answer your question thoroughly, the grade is reduced by 10 points. Creativity is a plus! 10 points. A more ambitious extend question will earn close to 10 points. An easier or smaller question will earn slightly fewer points. For a basic extension, you could rework the solve section with numbers that change the fairness or relationships significantly. In the original problem statement, the authors suggested keeping the problem the same, except that now Carly chooses the cheapest pair of shoes, which cost $60 (Sullivan et al, 2015, p. 90). Discuss your solution and whether this changes how you decide what's fair. For a more ambitious extension, you could test several different fairness scenarios and try to create a more general approach to deciding what is fair. For an even more ambitious extension, you could use a variable like x to represent one of the shoe costs, and try to create a general approach to deciding what is fair. Another strong extension would be to create several scenarios corresponding to different types of friendship, or different culture/class/gender-based attitudes towards fairness. Then solve the