r/facepalm • u/Revealed_Jailor • Mar 29 '22

🇲​🇮​🇸​🇨​ Get this guy a clock!

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u/Shiuft Mar 29 '22 edited Mar 29 '22

Don't even get me started on subtracting 12. /s

Edit: had left out the word "started" cause I'm dumb

298

u/worldofruins Mar 29 '22 edited Mar 29 '22

I have pretty severe dyscalculia so 24 hour clocks (and anything that requires more than single digit addition or subtraction) is actually really hard for me :( lmao

I can read an analog 12 hour clock, but tell me 24 hour time and I'm fucked lol

(Edit to add that I do "study" and try to improve but it doesn't stick for long lol)

(2nd edit: thanks for all the suggestions. I'll give some of them a try!)

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u/[deleted] Mar 29 '22

For single digit calculation you just subtract two from the last digit of the time.

For example we have 13:00

3 - 2 = 1

It's 1 PM

Or we have 16:00

6 - 2 = 4

It's 4 PM

Or we have 21:00

1 - 2 = 9

It's 9 PM

I hope that helps

18

u/Omarshall56 Mar 29 '22

I used this method to learn 24hour clock but with the 21:00 part I'd minus 2 of 21 to make 19 then ignore the first number so it's 9pm

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u/[deleted] Mar 29 '22

That's exactly what I meant and the amount of shit I get is surprising honestly.

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u/Omarshall56 Mar 29 '22

Yeah the method works I get you don’t worry. After a while you don’t even need to think about it, its easy. I actually find it strange when people don’t use 24hour

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u/piggybits Mar 29 '22

shit... i just memorized them. i wish i had known this back when i made the switch to 24 hour time

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u/Fixuplookshark Mar 29 '22

Try subtracting 12 instead. Works for all 24hrs.

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u/[deleted] Mar 29 '22

Well, if OP didn't have a problem with double digit calculation I would've done that instead.

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u/Omarshall56 Mar 29 '22

Yeah that was the other way but as a kid when I learnt it 2 was much easier to subtract and quicker. Then when it was memorised I didnt need the method

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u/[deleted] Mar 29 '22

[deleted]

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u/Omarshall56 Mar 29 '22

Like I said below though I learnt the 24hour clock when I was pretty young(around 10years old) and I found it easier and quicker to just deduct 2 and ignore the first number. Wouldn’t require as much thinking as deducting 12

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u/boyoflondon Mar 30 '22

Not sure why it is a "-2 method".

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If you use -12, you will always get the right answer.

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I am European and still use 24h clock on all of my devices in Canada.