You Go to a Carnival in Town Intending to Purchase

You go to a carnival in town intending to purchase rides for your children. When you get there they have an offer where everyone's first two rides are free. They obviously hope that the free rides will end up making them more money in the long run than if they charged for all rides. First, show on an indifference curve and budget line graph a solution that would make the free rides a bad idea for the company. Then, on a second graph, show a possible situation that would make the giveaway a success that should be repeated.