The Management Department recently purchased a small copier for faculty use. Although the workload of the office staff has improved somewhat, the secretaries are still making too many trips to the Dean’s office when the departmental copier is out of service. Sylvia, the departmental secretary, has been keeping track of failure rates and service times. With a mean time between failures of 100 hours and a mean time to repair of 24 hours, how much of the time is the new copier available for faculty use?