Elapsed Time Across Hours
To find elapsed time, compare the starting time and ending time carefully. The key idea is to count the hours passed, then adjust for any extra minutes.
1) Start with the hour change
- Count forward from the start hour to the end hour.
- If the time crosses into the next hour or day, keep counting in order.
- Write the difference in hours first.
2) Handle the minutes separately
- Subtract the starting minutes from the ending minutes.
- If the ending minutes are smaller, borrow 1 hour and add 60 minutes.
- Then simplify the result.
3) Combine the parts
- Put the hours and minutes together.
- If the answer can be simplified, reduce it to the simplest form required by the exercise.
Check your work
- Add the elapsed time back to the start time.
- You should get the ending time.
- Make sure the minutes are within 0–59.
A good habit is to work step by step instead of trying to do everything at once. This reduces mistakes and makes it easier to verify your answer.