How do we determine time interval?

We determine time interval by subtracting the final time from the initial time.

That is correct. It can also be measured with an electronic timer or a stopwatch.

Actually, you got it backwards. Subtract the initial time from the final time.

To determine the time interval between two points in time, you need to subtract the initial time from the final time. This can be done using the following formula:

Time Interval = Final Time - Initial Time

For example, let's say the initial time is 8:00 AM and the final time is 9:30 AM. To find the time interval, you would subtract 8:00 AM from 9:30 AM:

9:30 AM - 8:00 AM = 1 hour and 30 minutes

In this case, the time interval is 1 hour and 30 minutes. This method applies whether you're measuring time in minutes, hours, or any other unit.