Location problem: Alex, the owner of BikeRide, Inc., is considering expanding the current bicycle rental business by opening one new rental station. They have analyzed three potential locations. Each location is expected to have the same costs for bike maintenance, helmets, locks, and other materials, amounting to $1.20 per bike rental. The bike rental fee is $3.00 per bike in all locations. The rent and equipment costs for each location are as follows: $4,500 per month for Station X, $5,000 per month for Station Y, and $5,300 per month for Station Z. Determine the required rental volume at each location to achieve a monthly profit of $15,000