Question

Convert the following traditional times to military (international) times. \(1: 35 \mathrm{PM}=\)

Short answer

13:35

Step-by-step solution

Identify AM or PM

In a traditional 12-hour clock, the time given is 1:35 PM. The 'PM' indicates that it is in the afternoon, which means it needs to be converted to the military time format by adding 12 hours to the hour if it's PM.

Convert Hour to Military Time

Since the given time is 1:35 PM, add 12 to the hour to convert it to military time. Calculate: \(1 + 12 = 13\).

Write the Military Time

After converting the hour, the military time becomes 13:35. Unlike the traditional format, military time does not use AM or PM.

Key concepts

Time Conversion

Time conversion is an essential skill for understanding how different clock systems work. When converting time, you are changing it from one format to another, often from a 12-hour clock to a 24-hour clock, also known as military time. This change helps in understanding time without needing AM or PM distinctions.
Converting time involves different steps depending on the format being used. In general, the conversion requires you to identify whether it's AM or PM, then perform simple arithmetic operations to convert the time accurately. Being proficient in time conversion ensures clarity and avoids confusion, especially when communicating across different regions that use varied time formats.

12-hour Clock

The 12-hour clock format is commonly used in everyday life in many countries. This system divides the 24 hours in a day into two periods: AM (Ante Meridiem) and PM (Post Meridiem).
In this format, the cycle runs from 1 to 12 twice daily, from midnight to noon for AM and noon to midnight for PM.

• 12 AM to 11:59 AM refers to the morning hours.
• 12 PM to 11:59 PM covers the afternoon and night hours.

To convert from the 12-hour clock to the military time, especially for PM times, you need to add 12 to the hour.

24-hour Clock

The 24-hour clock, often referred to as military or international time, runs from 0 to 23. This format helps avoid ambiguity by eliminating the need for AM and PM.
It's prevalent in various professional fields, like the military, aviation, and the medical field. In this format:

• 00:00 - 23:59 represents the time within a day.
• Midnight is 00:00.
• Noon is 12:00.

When converting to military time, PM times involve adding 12 to the hour, so 1 PM becomes 13:00, and this system continues up to 24:00.

Mathematical Operations

Mathematical operations, such as addition and subtraction, are crucial when converting times between the 12-hour and 24-hour clocks. For PM times, you add 12 to the hour to switch to military time.
Here are a few basic operations:

• Adding 12 to convert from PM to military time: e.g., 1 PM is 1 + 12 = 13, resulting in a military time of 13:00.
• When dealing with AM, no addition is needed as the hour remains the same.

These simple operations ensure the correct conversion between formats, avoiding any misunderstanding in schedules or communication. Remember, once converted to 24-hour time, AM/PM indicators are unnecessary.