Question

7. A watch that loses a half-minute every hour was set to read the correct time at 05 45h on Monday. Determiner the time, in the 12-hour system, the watch will show on the following Friday at 19 45h.

Answer 1

Elapsed time=5 days and 14 hours=134 hous
Lost time = 134*0.5 min.=67 minutes
19:45-67 min. = 18:38 = 6:38 am.