00:00Hi kids! Today we will be learning adding and subtracting time duration. So let's get started.
00:11First of all, we should know that we write time as hours, minutes, seconds.
00:19Example, here it is 5 hours, 34 minutes, and 10 seconds.
00:25Now, we will learn how we can add time.
00:32We have to add 2 hours and 30 minutes to 5 hours and 20 minutes.
00:39While adding time, the simple rule is to add hours with hours and minutes with minutes.
00:47By adding hours, we get 7 hours, and by adding minutes, we get 50 minutes.
00:56So adding 2 hours, 30 minutes, to 5 hours, 20 minutes, we get 7 hours and 50 minutes.
01:07That is, 7 hours and 50 minutes.
01:10Let's take another example.
01:15We have to add 5 hours, 10 minutes, to 1 hour, 15 minutes.
01:24Adding hours, we get 6 hours, and adding minutes, we get 25 minutes.
01:31So, our answer is 6 hours, 25 minutes.
01:38Now, let's take another example.
01:41We have to add 3 hours, 40 minutes, to 1 hour, 55 minutes.
01:48Adding hours, we get 3 plus 1 equals 4 hours.
01:54And adding minutes, we get 40 plus 55 equals 95 minutes.
02:02Here, the minutes are more than 60, and we know 60 minutes make an hour.
02:09So, subtract 60 from minutes and add 1 to hours.
02:14So, 95 minus 60 equals 35 minutes.
02:21And adding 1 to hours, we get 5 hours.
02:26So, our answer is 5 hours, 35 minutes.
02:32So, we learned, add hours to hours and minutes to minutes.
02:38But if minutes are more than 60, subtract 60 from minutes and 1 to hours.
02:47Now, let's take another example.
02:51We have to add 6 hours, 17 minutes, to 3 hours, 45 minutes.
02:59Adding hours, we get 9 hours.
03:02And adding minutes, we get 62 minutes.
03:06Here, the minutes are more than 60, and we know 60 minutes make an hour.
03:14So, add 1 to hours and subtract 60 from minutes.
03:20Subtracting 60 from minutes, we will be left with 2 minutes.
03:25And, by adding 1 to hours, we get 10 hours.
03:31So, our answer is 10 hours and 2 minutes.
03:38Kids, now let's learn how we can subtract time.
03:42We have to subtract 5 hours, 20 minutes from 7 hours, 45 minutes.
03:52While subtracting time, the same rule is to be followed.
03:57Subtract hours from hours and minutes from minutes.
04:01Subtracting hours, that is, subtracting 5 hours from 7, we are left with 2 hours.
04:11Now, subtract minutes from minutes.
04:14Subtracting 20 from 45 minutes, we are left with 25 minutes.
04:20So, our answer is 2 hours, 25 minutes.
04:27Now, let's take another example.
04:29We have to subtract 8 hours and 50 minutes from 10 hours and 55 minutes.
04:38Subtracting hours from hours, that is, subtracting 8 from 10, we are left with 2 hours.
04:47Subtracting minutes from minutes, that is, subtracting 50 minutes from 55 minutes, we are left with 5 minutes.
04:57So, the answer is, 2 hours, 5 minutes.
05:04Now, let's take another example.
05:06We have to subtract 4 hours, 40 minutes from 5 hours, 30 minutes.
05:15Now, here is a tricky question.
05:19We have to subtract hours from hours.
05:21Subtracting 4 from 5, we are left with 1 hour, but we have to subtract 40 minutes from 30 minutes.
05:31Now, here is something to learn.
05:33If the minutes to be subtracted are more than minutes from which we have to subtract,
05:39add 60 minutes to the minutes from which we have to subtract, and subtract 1 from hours.
05:47Add 60 to 30, and the minutes will become 90, and subtract 1 from hours.
05:57So, the time duration will remain the same.
06:01It will be 4 hours and 90 minutes.
06:06Now, you can subtract minutes from minutes.
06:10Now, subtracting hours, we get 4 minus 4 equals 0 hours.
06:19Now, subtracting minutes, 90 minus 40 equals 50 minutes.
06:25Our answer is 50 minutes.
06:30Now, let's take another example.
06:33We have to subtract 5 hours, 30 minutes from 7 hours, and 20 minutes.
06:39While subtracting time, we have to subtract hours from hours, and minutes from minutes.
06:46But here, we have to subtract 30 minutes from 20 minutes.
06:52So, what we do in such cases is...
06:56Add 60 minutes to the minutes from which we have to subtract, and subtract 1 from hours.
07:04That is, subtract 1 from 7.
07:07It will be 6 hours.
07:10And add 60 minutes.
07:13It will be 80 minutes.
07:15So, it won't change the time.
07:17It will be 6 hours and 80 minutes, which is same as 7 hours and 20 minutes.
07:25But we can easily subtract 5 hours and 30 minutes from...
07:316 hours and 80 minutes.
07:34Subtracting 5 hours from 6 hours, we get 1 hour.
07:40And subtracting 30 minutes from 80 minutes, we get 50 minutes.
07:46So, our answer is 1 hour, 50 minutes.
07:51So, kids, today we learned how we can add and subtract time durations.
07:57Now, you may go ahead and take a quiz to learn more.
08:01Bye-bye!
