How to Subtract Time Hours Minutes and Seconds with Examples
How to Find the Subtraction in Time?
Time is a varying factor. In a day, we have 24 hours, 1440 minutes, and 86400 seconds. Now, to calculate the time difference, we use the subtraction operator. For example, if Neha started her journey at 10:00 a.m. and reached her home at 12:00 p.m., what was the time difference between Neha’s journey from home to office, and vice versa? Well, it's 12: 00 − 10: 00 = 2hrs. This means that Neha took two hours to reach her office.
Similarly, we can find the time subtraction across various journeys. So, let us understand these with the help of illustrating examples.
Examples of Time Addition and Subtraction
Before starting with the difference in time, let us see the addition of time:
Example: Add 4:45 and 3:10.
Solution: On adding 4 and 3, we get 7 and 45 + 10 gives 55. So, we have 7:55.
Now, let us take another example:
Example: Add 5:50 and 4:30.
Solution: On adding 5 and 4, we get 9. Also, on adding 50 and 30, we get 80.
Here, we can see that 80 > 60. We can write 80 as 80 = 60 + 20. This means 80 minutes is 1 hr and 20 minutes.
Here, 9 hrs + 1 hr + 20 minutes is equal to 10 hrs 20 minutes or 10:20 is our answer.
Now, if we wish to find the difference between 5:50 and 4:30, we have the following steps:
5 − 4 = 1 hr
50 − 30 = 20 minutes
Here, the difference or the time subtraction comes out to be 1 hr 20 minutes or 1:20.
Time Subtraction Solved Examples
Example 1: Subtract 3:45 and 1:14.
Solution:
Subtraction of hours: 3 − 1 = 2 hours
Subtraction of minutes: 45 − 14 = 31 minutes
So, 2 hrs 31 minutes is the answer.
Example 2: Subtract 4:10 and 6:15.
Solution:
Subtraction of hours: 4 − 6 = −2
Subtraction of minutes: 10 − 15 = −5
Here, we can see that hours is less than 0, so we have:
− 2 + 24 = 22
Adding 60 to minutes: − 5 + 60 or 60 − 5 = 55 Minutes
Hence, the time subtraction for 4:10 and 6:15 comes out to be 21:55.
FAQs on Subtraction in Time with Borrowing Method
1. What is subtraction in time in Maths?
Subtraction in time means finding the difference between two given times to calculate duration. It tells us how much time has passed from a start time to an end time. This concept is commonly used in elapsed time problems and real-life situations like calculating travel time or study hours.
- Identify the start time and end time.
- Subtract hours from hours and minutes from minutes.
- Adjust if borrowing is needed.
2. How do you subtract time step by step?
To subtract time, subtract the minutes first, then the hours, borrowing 1 hour = 60 minutes if needed. Follow these steps:
- Step 1: Write the times in hours and minutes format.
- Step 2: Subtract minutes. If top minutes are smaller, borrow 1 hour = 60 minutes.
- Step 3: Subtract hours.
3. How do you subtract time when borrowing is required?
When minutes in the top time are smaller, borrow 1 hour (60 minutes) from the hours column. Example: 6:15 − 2:40.
- Borrow 1 hour from 6 hours → 5 hours and 75 minutes.
- 75 − 40 = 35 minutes.
- 5 − 2 = 3 hours.
4. What is the formula for finding elapsed time?
The formula for elapsed time is Elapsed Time = End Time − Start Time. This formula is used in subtraction in time problems.
- Convert times to the same format (12-hour or 24-hour).
- Subtract minutes and hours carefully.
- Adjust for borrowing if required.
5. How do you subtract time in 24-hour format?
To subtract time in 24-hour format, subtract hours and minutes directly without AM/PM confusion. Example: 18:30 − 14:45.
- Borrow 1 hour → 17 hours 90 minutes.
- 90 − 45 = 45 minutes.
- 17 − 14 = 3 hours.
6. How do you subtract hours and minutes separately?
You subtract hours and minutes separately by aligning them in columns and subtracting minutes first. Example: 9:50 − 4:25.
- Minutes: 50 − 25 = 25 minutes.
- Hours: 9 − 4 = 5 hours.
7. Can you give an example of subtraction in time word problems?
Yes, subtraction in time word problems helps find how long an activity lasted. Example: A movie starts at 2:15 PM and ends at 4:05 PM.
- Borrow 1 hour → 3 hours 65 minutes.
- 65 − 15 = 50 minutes.
- 3 − 2 = 1 hour.
8. What are common mistakes in subtraction of time?
A common mistake in subtraction of time is forgetting that 1 hour = 60 minutes, not 100 minutes. Other mistakes include:
- Not borrowing correctly when minutes are smaller.
- Mixing 12-hour and 24-hour formats.
- Ignoring AM and PM differences.
9. How do you subtract time across AM and PM?
To subtract time across AM and PM, first convert both times into the same format, preferably 24-hour time. Example: 10:30 AM to 1:15 PM.
- Convert 1:15 PM to 13:15.
- 13:15 − 10:30.
- Borrow → 12 hours 75 minutes.
- 75 − 30 = 45 minutes; 12 − 10 = 2 hours.
10. Why is subtraction in time important in daily life?
Subtraction in time is important because it helps calculate duration and elapsed time in everyday activities. It is used for:
- Finding travel time between places.
- Calculating working or study hours.
- Scheduling events and appointments.
