I know the answe is $9,250 but dont know how to calculate

Oaks Company has two support departments, Maintenance Department (MD) and Personnel Department (PD), and two producing departments, P1 and P2. The Maintenance Department costs of $20,000 are allocated on the basis of standard service used. The Personnel Department costs of $4,500 are allocated on the basis of number of employees. The direct costs of Departments Pl and P2 are $9,000 and $15,000, respectively. Data on standard service hours and number of employees are as follows: Using the sequential method, if the support department with the highest percentage of interdepartmental service is allocated first, the cost of the support departments allocated to Department P2 is