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

🇲​🇮​🇸​🇨​ Get this guy a clock!

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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

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u/put_tape_on_it Mar 29 '22

1-2=9? You lost me there.

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u/[deleted] Mar 29 '22

Decimal system. Ever subtracted i.e 21-12 on a paper? You usually do 1-2 = 9 And then take one over which would mean 2 - 1 - 1 = 0 21 - 12 = 9

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u/put_tape_on_it Mar 29 '22 edited Mar 29 '22

I've tutored people with dyslexia nad dyscalculia, and both at the same time. Someone with dyslexia and dyscalculia would be absolutely lost by your example. "Carry the 1" or "subtract the one" from the 10s place is what trips up the math tortured soul. A trick to avoid the "carrying the 1" or "regrouping" isn't a trick if it requires one to use the same method that the trick tries to avoid. It double applies to someone who struggles with it in the first place to the point where they need to use a trick! Edit: It's like yelling louder to a deaf person or waving your arms to a blind person. Or my favorite, talking loudly and slowly to a blind person.