Final answer:
When converting 3:00 pm Greenwich Mean Time to Military time, it is expressed as 1500 hours. This is due to the 24-hour clock system used in Military time that counts the hours from 0000 to 2359.
Step-by-step explanation:
If it is 3:00 pm Greenwich Mean Time (GMT), also known as Coordinated Universal Time (UTC) or Universal Time (UT), it is expressed in Military time as 1500 hours. Military time, also known as the 24-hour clock, is a timekeeping system that runs from midnight (0000 hours) to 23:59 hours, eliminating the need for the a.m. and p.m. designations.
This system is used by military and other entities around the world to avoid ambiguity. Since 3:00 pm falls in the post-meridian (p.m.) period of the day, we simply add 12 to the 3:00 hour to convert it to military time, which results in 1500 hours.