Answer: Here are a few ways that you could apply expressions or equations to a camping trip.
The cost of renting a cabin could be: C = 50N + 70, where C is the cost and N is the number of nights.
The number of tents needed could be: T = P/3, where T is the number of tents and P is the number of people going.
The amount of marshmallows needed could be: M = 5P, where M is the number of marshmallows and P is the number of people.