Trick for Adding Time
Have you ever faced any problem in adding time?
If you have ever have faced the slightest difficulty in adding time or duration expressed in hours and minutes, this trick is meant for you.
Say you have to add 4 hours 55 minutes and 2 hours 40 minutes.
Make 4 hours 55 minutes into one number, which will give us 455 and do the same for the other number, 2 hours 40 minutes, giving us 240.
Shortcut Trick to Add Two Numbers
Simply add these two numbers together:
455
240
------
695
What you need to do is add 40 to the above result. No matter what the hours and minutes are, just add the constant 40 to the total obtained by adding the time in above manner.
695 + 40 = 735; this means 7 hours 35 minutes.
Be Careful
If there is no carryover from minutes to hours and the minutes digits are less than 60, don't add 40. What you get after first step is your final answer. Say for example, if you have to add 2 hours 20 minutes and 3 hours 35 minutes:
220
335
------
555
So you straight away get your answer as 5 hours 55 minutes.
Another Illustration
Similarly, if someone is coming after 3 hours 55 minutes and right now the time is 1:35PM, you can use the above method to find the time of arrival.
355
135
-----
490
Adding 40 + 490, we get 530. Hence the person will arrive at 5:30PM.
More than two duration
This method can easily be extended for adding more than two time/duration.
So say for example, if you have to add 3 hours 40 minutes, 2 hours 25 minutes and 1 hour 55 minutes, we can do it like this:
340
225
155
------
720
Adding 40 twice to 720, we get 800. Hence, the answer is 8'o Clock.
For more information on math classes, consider looking into online universities
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September 19th, 2012 - 23:23
what for 3:45 + 2:30 + 2:50
April 12th, 2012 - 19:43
nyc tricks
April 8th, 2012 - 18:37
thanx u 4 dis tricky trick i;ve been looking 4 the methods of adding n subtracting times
February 21st, 2012 - 01:37
???? ???? ?????? ????? ????? ???? ?????? ????? ????? ????? ?? ?? ????? ????? ???? ???? ??? ????? ? ?????? 3 ? 20 ???? ? 2 ? 50 ???? ?? ?? ?????? ?? ??? 320+250+40= 610 ????? 6 ? 10?? ?????? ???? ?? “????? ??? ?????” ?????? ?? ?? ????? ?? ??? ???
January 21st, 2012 - 10:28
Sir,
I was using the trick & tried on several examples but I was struck to one where I got total of last two digits as 60 ex-
340
+265
+155
———
760
now should I take it as 8.00?
January 25th, 2012 - 21:54
U must add 40 twice time as the duration is more than two….
January 26th, 2012 - 09:20
thanks..nw I got
February 17th, 2012 - 23:34
if there are additions of five times then how much will be the addition of 40 if the answer is 765
February 23rd, 2012 - 17:19
7:60+40+40= 840 = 8:40
March 24th, 2012 - 14:54
Hi Pallavi,
You were adding 265 and 155. now please tell mw what is 265? either it should be 2.59 or 3.05.
Rgds/Ramanaiah
March 25th, 2012 - 18:52
Is 1.345 meter is correct ? No. because we always write meter and centimeter in different position i.e. 345 cm will be written as 3 meter and 45 cm. So 1.345 meter is actually 4 meter (3 + 1 meter=4 meter) and 45 cm.
Similarly 265 is may will be written as 305 (65 minutes= 1 hours+ 05 minutes)
(2+1=3 hours)
i.e. three hours and 5 minutes.
June 13th, 2012 - 18:35
dear there cannot be any time like 2 hours 65 minutes when we talk abt the time or if it is so u make 2 h 65 mts as 3 hours and 5 minutes as 340+305+155=800
Now, as the sum crossed 60 once so add 40 once to 800=840 so the correct time would be 840
January 4th, 2012 - 11:13
yes nice and thanks
December 12th, 2011 - 16:21
please i had just checked the interesting to do.. just let me give a chance to say on such farmulaes
December 5th, 2011 - 15:32
It is very useful. First I was confused about 1.20+1.30=2.50+40= 2.90
Now it is clear.
Thanks..
February 16th, 2012 - 21:22
no its wrong because when in ur ans minute is more than 60 than only u hav to add 40 ok ohter
December 5th, 2011 - 15:31
Thanks…
It was new for me..
November 25th, 2011 - 16:24
very useful trick
November 28th, 2011 - 23:38
very useful
November 23rd, 2011 - 16:35
Wonderful
November 11th, 2011 - 20:12
nice trick
November 11th, 2011 - 04:06
If you have two numbers to add and the last two
digits of the sum are less than 60, you can’t add
the 40.
Example: 2 hours and 15 minutes and 3 hours
and 40 minutes
215+340=355
If you add 40, it will make it 395, which is incorrect.
In your example for three numbers, they should
have added to 720. If you add 40, it will add to 760
and not 800.
November 11th, 2011 - 08:56
Thanks Michael,
I have made the necessary changes in the post above. I appreciate your contribution.
November 21st, 2011 - 14:30
@michael
215+340 is 555
it’s not 395
read the first instruction with name be carefull
December 12th, 2011 - 16:19
we can directly add any numbers like 2-15 + 3-40 = 5-55 is ans
and say 3-40+2-25+1-55 =6-120 now if we divide 120 by 60 then maximum quotient is 2 and remainder is zero this means 6+2-00=8-00
now again say 3-42+2-27+1-57 =6-126 now if we devide 126 by 60 then maximum quitent is 2 and remainder is 6 this means 6+2-06=8-06
we can add as much like 2-10+3-15+4-20+5-40=14-85 and by dividing 85 by 60 oraly maximum quotient is 1 and remainder is 25 this means
14+1-15=15-25
January 21st, 2012 - 10:17
thanks..I will also remember this quotient method too…keep posting such tricks….
January 20th, 2012 - 21:33
Very Nice Micheal…Tat was very minute thing but u pointed out d thing…It really helped me to grasp the trick…Thanks
November 10th, 2011 - 11:41
awesome blossom!!!!~~~~!!!
November 10th, 2011 - 10:45
~Wow~
November 10th, 2011 - 10:36
Best Trick ever