Legend:

P1 = 1
P2 = 2
...
each digit indicates a unit of time in the Gantt chart.



FCFS
----

11111111111222222222333333344444555

T = [(0-0)+(11-2)+(20-4)+(27-6)+(32-8)] / 5
  = (0+9+16+21+24) / 5
  = 70 / 5
  = 14


SJF
---

11111111111555444443333333222222222

T = [(0-0)+(11-8)+(14-6)+(19-4)+(26-2)] / 5
  = (0+3+8+15+24) / 5
  = 50 / 5
  = 10



SRTF
----

such as SJF