How To Add and Subtract Time in Hours and Minutes

TL;DR

Add and subtract time by calculating the minutes and hours separately, converting 60 minutes into one hour when adding, or borrowing one hour as 60 minutes when subtracting. For example, six hours 35 minutes plus four hours 47 minutes equals 11 hours 22 minutes. Read on for worked examples that show carrying, conversion, and borrowing.

Transcript

in this video we're going to talk about how to add and subtract time in the units of hours and minutes so let's say if we have this problem we have 5 hours 18 minutes and we wish to add that to three hours and 24 minutes first we need to add these two numbers because the units match eight plus four is twelve we're going to write the 2 carry over th... Read More

Key Insights

• ⌛ Adding time in hours and minutes involves adding the minutes and carrying over extra hours.
• ⌛ When minutes exceed 60, convert them into hours and subtract 60 from the minutes value.
• ⌛ Subtracting time may require borrowing hours and increasing minutes by 60 to avoid negative values.
• ⌛ Practice examples help understand the process of adding and subtracting time effectively.
• ⌛ Manipulating hours and minutes separately facilitates accurate calculations.
• ⌛ Understanding the concept of borrowing and converting between hours and minutes is crucial.
• ⌛ Time management skills are essential for performing calculations with time accurately.

Questions & Answers

Q: How do you add time in hours and minutes?

Add the minute values first, then add the hour values. If the resulting minutes are 60 minutes or more, convert 60 minutes into one hour and combine it with the hours.

Q: What is five hours 18 minutes plus three hours 24 minutes?

The minutes add to 42 minutes, and the hours add to eight hours. The result is eight hours 42 minutes.

Q: What is six hours 35 minutes plus four hours 47 minutes?

The minutes add to 82 minutes, while the hours add to 10 hours. Converting 60 minutes into one hour leaves 22 minutes, so the result is 11 hours 22 minutes.

Q: What should you do when the minute value is 60 minutes or more?

Convert 60 minutes into one hour. Add that hour to the hour total and keep the remaining minutes.

Q: How do you subtract time in hours and minutes?

Subtract the minute values and the hour values separately. If the starting minute value is smaller than the minute value being subtracted, borrow one hour and add 60 minutes to the starting minutes.

Q: What is nine hours 54 minutes minus three hours 31 minutes?

Subtracting 31 minutes from 54 minutes gives 23 minutes. Subtracting three hours from nine hours gives six hours, so the result is six hours 23 minutes.

Q: Why do you borrow an hour when subtracting time?

Borrow an hour when subtracting the minute values directly would produce a negative result. The borrowed hour becomes 60 minutes, which is added to the starting minute value before subtraction.

Q: What is eight hours 27 minutes minus four hours 39 minutes?

Borrow one hour from eight hours, leaving seven hours, and add 60 minutes to 27 minutes to get 87 minutes. Then 87 minutes minus 39 minutes is 48 minutes, and seven hours minus four hours is three hours, giving three hours 48 minutes.

Summary & Key Takeaways

• Definition: One hour equals 60 minutes.

• Number: Five hours 18 minutes plus three hours 24 minutes equals eight hours 42 minutes.

• Number: Six hours 35 minutes plus four hours 47 minutes initially gives 10 hours 82 minutes.

• Number: Converting 60 minutes from 82 minutes leaves 22 minutes and adds one hour.

• Number: Six hours 35 minutes plus four hours 47 minutes equals 11 hours 22 minutes.

• Number: Nine hours 54 minutes minus three hours 31 minutes equals six hours 23 minutes.

• Compare: When 27 minutes is less than 39 minutes, borrow one hour and increase 27 minutes to 87 minutes.

• Number: Eight hours 27 minutes minus four hours 39 minutes equals three hours 48 minutes.