Add Time
The addition of time is similar to addition of numbers, but here, we need to consider the conversion for the addition of time. One unit of time is made up of 60 subunits and is different from the other mathematical units of conversion. A time of 1 hour is equal to 60 minutes, and a time of 1 minute is equal to 60 seconds. Also, the addition of time comes up with an additional challenge of the format in which the time is expressed. Time is expressed in either a 12hour format or a 24hour format.
There are numerous instances in our daily life, where this concept of the addition of time is required. For instance, for finding the total time of travel across different modes of transport, to find the total time spend by the student across the different activities in a school, we need to use this concept of addition of time. Let us learn more about add time in this lesson.
1.  Adding Time 
2.  Adding Hours and Minutes 
3.  Subtracting Time 
Adding Time
Adding time in math is the process of adding distinct units of time such as hours, minutes, and seconds and then integrating them together. The normal addition has a unit broken into 1, 10, 100, etc subunits, and in time the unit of time is broken into 60 subunits. This distinctiveness sometimes makes the addition of time slightly difficult. Further the addition of time can be practically done as the normal addition, with the conversion of values more than 60 into higher units. The following table represents the unit values of time.
Units of time  Value 

1 day  24 hours 
1 hour  60 minutes 
1 minute  60 seconds 
Adding Hours and Minutes
Adding time by hours and minutes is very simple if we know their conversion. First, add all the hours of the two times. Now add the minutes of the two given times. Further write the time obtained in hours: minutes format. As an example let us add the set of two times, 9:10 and 1:15. Adding hours 9 and 1 is equal to 10. Further adding the minutes 10 and 15 is equal to 25. Further writing the calculated hours and minutes together we have 10:25. In some cases, if the added minutes are more than 60 which cannot take it directly. Instead, we must convert that into hours by subtracting the additional minutes. Let us see this with another example. Add 7:45 and 3:25. Here we have 7 + 3 = 10, and 45 + 25 = 70. These 70 minutes cannot be taken directly. We know that 1 hour = 60 minutes. The 70 minutes can be written as 60 minutes + 10 minutes, or 1 hour and 10 minutes. Therefore the time is 11 hours and 10 minutes or 11:10.
Addition of Time  24 Hour Clock: The 24hour clock is preferably followed in the United States and is called military time. In the United Kingdom, the 24hour clock is referred to as continental time. In some of the countries, it is referred to as railway time.
Add 21:15 and 2:30. We first add the hours of 21 + 2 = 23 hours, and then add the minutes as 15 + 30 = 45 minutes. Therefore the time is 23: 45. Let us look at another example of adding time in a 24hour format. Add 2:30 and 18:55. First adding the hours we have 2 + 18 = 20. Now adding the minutes we have 30 + 55 = 85. But 85 minutes cannot be taken directly. The 85 minutes is equal to 60 min and 25 minutes. Or we have 1 hour and 25 minutes. Adding this 1 hour to the earlier 20 hours we have 21 hours. Therefore writing the hours and minutes together we have 21: 25.
Addition of Time  12 Hour Clock: The 24hour clock is divided into two periods as a.m (antimeridiem) and p.m (postmeridiem). In a 12hour clock, midnight 12 a.m is considered as the start of the day. The same addition procedure is followed in a 12hour clock also. Now let us learn about subtracting time.
Subtracting Time
The subtraction of time is almost the same as the addition of time. For this, we follow some of the simple steps. First, subtract the hours, and then subtract the minutes. Further, write the resultant answer of hours and minutes. Let us look at this with a simple example. Let us subtract 5:45 from 7:55. First, let us subtract the hours 7  5 = 2, then we can now subtract the minutes 55  45 = 10. The result can be written together as 2:10.
Let us look at another example to subtract 6:45 a.m from 12:10 p.m. We observe here that 45 minutes is more than 10 minutes. So, for carrying on subtraction, we need to borrow minutes from 12 hour and give to 10 minutes. By borrow 60 minutes from 1 hour, we have 12 hours 10 minutes is equal to 11 hours, 60 minutes + 10 minutes, or 11 hours and 70 minutes. Now, we have 70 minutes which is more than 45 minutes. So, we proceed with the following subtraction.
Therefore we have 5 hours and 25 minutes from 6:45 a.m to 12:10 p.m. So, we have learned to add and subtract time.
Let us look at the following tips and tricks on time.
 Add all the hours and minutes to calculate the total time. Similarly, subtract all the hours and minutes to calculate the time.
 While adding minutes, if it goes beyond 60, then remove 60 and consider the remaining minutes as total. Those removed 60 minutes are converted to an hour and added with hours.
 While subtracting minutes, if the minutes are negative then add 60 minutes with them and consider their total as minutes. Those added 60 minutes which in turn considered an hour are removed from the total hours.
Solved Examples on Add time

Example 1: Anna plans to visit a zoological park. She takes a cab at 3.45 P.M. It takes about 1 hour 5 minutes to reach her destination. At what time does Anna reach the zoological park?
Solution:
The initial time is 3.45 P.M. And the travel time is 1 hour 5 minutes. Adding the hours we have 3 + 1 = 4 hours and adding the minutes we have 45 + 5 = 50 minutes. Therefore Anna reaches the Zoological park at 4:50 PM.

Example 2: Ruth started his homework at 6:30 P.M and completed it at 8 P.M. How many hours and minutes were spent by Ruth to complete her homework?
Solution:
Subtract 6:30 from 8:00. So we have 8 hours = 7 hours and 60 minutes. Therefore (7 hours 60 minutes  6 hours 30 minutes) is equal to 1 hour and 30 minutes. Therefore Ruth spends 1 hour and 30 minutes completing her homework.
FAQs on Add Time
How do you Add Seconds?
Adding seconds is similar to any other addition. But here for value beyond 60 we have to convert the seconds into minutes. Let us understand this with a simple example. If we add 40 seconds and 35 seconds, we have 40 + 35 = 75 seconds, which is equal to 60 seconds and 15 seconds. This value is equal to 1 minute and 15 seconds.
What is the Addition of Minutes in Time?
The addition of minutes is similar to any other addition. Here the unit of 60 minutes is equal to 1 hour. Hence the time more than 60 minutes are converted to hours. Let us understand this with a simple example. Addition of 50 minutes and 40 minutes. This addition is equal to 50 + 40 = 90 minutes. This 90 minutes can be converted into 60 minutes, and 30 minutes. Therefore the sum of the minutes is equal to 1 hour and 30 minutes.
How to Add Time?
The addition of time is slightly different from the addition of another kind of quantity. Here the addition of 1 unit is made of 60 subunits. Or 1 hour is equal to 60 minutes, 1 minute is equal to 60 seconds. Let us understand by adding two simple time values of 2 hours 15 minutes and 3 hours 30 minutes. Here we add the hours first separately and then the minutes separately. The hour values on addition we have 2 hours + 3 hours = 5 hours, and the sum of the minute values is 15 minutes + 30 minutes = 45 minutes. Therefore the total time is 5 hours and 45 minutes.
Can we Add Hours and Minutes?
The hours and minutes are calculated by applying the following conversion unit of 1 hour is equal to 60 minutes. Also if the value of a minute is more than 60 minutes, it is converted into hours. Let us sum this with a simple example of finding the sum of 5 hours 20 minutes and 50 minutes. Here we keep the hours without any change and add only the minutes 20 minutes + 50 minutes is equal to 70 minutes. The 70 minutes is equal to 60 minutes + 10 minutes or 1 hour and 10 minutes. Therefore the sum of the times is equal to 6 hours and 10 minutes.
How is the Addition of Time Different From Normal Addition?
The addition of time is slightly different from the normal addition. The prime reason for this difference is because a unit of time is made up of 60 subunits. For conversion, we have 1 hour of time is equal to 60 minutes, and 1 minute is equal to 60 seconds. Let us understand this by performing a simple addition of 4 hrs, 30 min, and 3 hrs, 40 min. (4 hrs, 30 min) + (3 hrs, 40 min) = (4 + 3)hrs , (30 + 40)mins = 7hrs, 70mins, = 7hrs, (60 + 10)mins, 7hrs, 1hrr + 10min = (7 + 1)hr, 10min = 8hrs, 10 min. The conversion of time is to be rightly taken into account while adding time.
How Many Hours are there in Two Days?
There are 24 hours in a day and in two days we have 2 x 24 = 48 hours. Therefore we have 48 hours in 2 days.
What is the Easiest Way to Add Time?
The easiest way to add time is to add the hours, minutes, and seconds separately. Here we need to distinctly add these three units separately, and write them together as an answer. For this, we need to also consider the conversion unit of 1 hour is equal to 60 minutes and 1 minute is equal to 60 seconds.
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