Adding and Subtracting Time

The steps to add times are the following:

• Add the seconds. If the seconds is more than 60 then subtract 60 from it and add 1 to the minute.
• Add the minutes. If the minutes is more than 60 then subtract 60 from it and add 1 to the hour.
• Add the hours.

  Example:

  
• Sometimes hour may also end up to large.
• If the hour is more than 24 then subtract 24 from it and add 1 day.

Recall the relation between the units of time:

Subtraction of time

The steps to subtract times are the following:

• Subtract the seconds. If the seconds is negative then subtract 60 from it and remove 1 from the minute.
• Subtract the minutes. If the minutes is negative then subtract 60 from it and remove 1 from the hour.
• Subtract the hours.

Example:

11: 70 – 06: 45

Elapsed Time

Elapsed time is the time between the start of the event and the end of the event. Using elapsed time, we can find the duration of any event or interval between two events.

Steps to find the elapsed time:

• Note the start time.
• Note the end time.
• Calculate the difference between the start time and the end time.

Example:

The show started at 2: 15 pm and ends at 6: 30 am. Find the duration of the show.

Answer:

Hence, the duration of the show is 04: 15 minutes.