Find Elapsed Time

We will look into two methods to find elapsed time:

1. Using a timeline or number line to visualize and calculate the elapsed time.
2. Convert the time to a 24-hour clock and perform the calculation.

Using a Timeline or Number Line
The following diagram shows how to solve an elapsed time problem using a number line. Scroll down the page for step by step solutions on how to find the elapsed time.

1. Draw a horizontal line and mark the start time.
2. Start at the beginning time and jump forward in manageable chunks of time.
3. Write the amount of time you jumped above each segment.
4. Continue until you reach the ending time.
5. Add up all the time intervals you marked above the timeline to get the elapsed time.

Time Worksheets
Practice your skills with the following worksheets.
Printable Elapsed Time Word Problems
Online Elapsed Time Word Problems
Time Worksheets

Elapsed Time: How to Solve Elapsed Time on a Number Line
How to find out how much time has elapsed by using a number line?

Example:
Emily had soccer practice after school today. The green clock shows what time practice began. The yellow clock shows what time it ended. How much time did Emily spend in soccer practice today?

• Show Video Lessons

Calculating Elapsed Time
Calculate the time interval between two given times, and also the time before or after a given time, knowing the duration.

• Show Video Lessons

Elapsed Time - Number Line
How to find elapsed time on a number line?

• Show Video Lessons

Using the 24-hour Clock
Converting to a 24-hour clock (military time) can simplify elapsed time calculations, especially when dealing with AM/PM changes.

1. Convert both times to 24-Hour Time
   If the given time is in AM then keep the time the same.
   If the given time is in PM then add 12 to the hour.
   Exception: 12 PM is 12:00, and 12 AM is 00:00.
   
2. Subtract the start time from the end time to calculate the elapsed time. If the end time is earlier than the start time (indicating it’s the next day), add 24 hours to the end time before subtracting.

Try the free Mathway calculator and problem solver below to practice various math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.

We welcome your feedback, comments and questions about this site or page. Please submit your feedback or enquiries via our Feedback page.