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"Hey! If I were to add 6 to 13 I would get 7!", said Patrick slowly as he blew a stream of suspiciously maroon smoke out through his left nostril while calmly stabbing a funny-looking cigarette into an upturned potty.
"Dude.... That is awesome!" giggled Frank.
Provided that Patrick is not tripping, how does his statement make sense?

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closed as too broad by Deusovi, manshu, itriedacrab, March Ho, Alconja Feb 25 at 2:54

There are either too many possible answers, or good answers would be too long for this format. Please add details to narrow the answer set or to isolate an issue that can be answered in a few paragraphs.If this question can be reworded to fit the rules in the help center, please edit the question.

up vote 32 down vote accepted

Patrick has:

An extremely alkali solution (something bleach-like) of pH 13
If he adds the correct amount of a moderately acidic solution (say, coffee or urine) of pH 6

He'll get:

A neutral solution of pH 7
And Frank saying, "You really do have a plan! Yeah science!"

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This answer should get more upvotes... – ABcDexter Feb 24 at 18:44
Agreed on ABcDexter, more upvotes! – Alex Feb 24 at 20:26

Okay, well how about

Base 5031

If we work with this, then

$6_{5031} + 13_{5031} = 19_{5031} = 5040_{10} = 7!$

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It might be better to show that the entire equation is valid in base 5031, since $(7_{5031})! === (7_{10})!$ – March Ho Feb 25 at 2:13
Because they are obviously equivalent (with 7 representable in both bases), I found it unnecessary to explicitly mention. – Ian MacDonald Feb 25 at 13:50

This is

base 12 clock arithmetic. If you start with 6 o'clock and add 13 hours you get 7 o'clock.

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As far as i understand this, he is adding 6 to 13 and not 13 to 6... There can't be a 13 as augend in a base12 clock arithmetic – Wa Kai Feb 24 at 14:07

It's a bit of a stretch but it might be that

they are filling baggies with carefully measured amounts of... oregano. Perhaps because they and many of their friends are chefs.

Patrick is announcing that

as the thirteenth baggie has only a single ounce of oregano...

If [he] were to add six to thirteen, [he] would get seven

Certainly he is not tripping. His mastery of the subjunctive tense shows that he is of clear mind.

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Who buys their spices in seven-ounce bags? – question_asker Feb 24 at 14:28
yeh.... maybe they are seven-pound bags?? :-) – Ben Feb 24 at 15:00
In my youth some of my friends were fond of and oregano-like substance that they bought by the ounce in baggies. – Hugh Meyers Feb 25 at 12:19

Well, they both have the...

munchies, and they are looking at a take-away menu from their local Chinese.

Patrick noticed that

No. 6 on the menu is Shrimp, No. 13 on the menu is Fried Rice, and No. 7 is Shrimp Fried Rice. So he's quite right, if you add 6 to 13 you get 7.

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Another example of question being too board? However, hmm....shrimps.... upvote! – Alex Feb 24 at 20:28

I'm stealing Tom's answer =) :

it's 13:00 pm, adding 6 hrs will result in 19:00, which is 7 o'clock

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"one should not steal"...that's why another one has to steal his answer too. :p – manshu Feb 24 at 15:36
@manshu I was editing my answer from "steal" to "borrow" when I see your comment, and now I stopped editing – Alex Feb 24 at 15:39
@Alex: No, Tom got the answer. – Deusovi Feb 24 at 18:47
there's no such thing as 13:00 pm. 1:00 pm is 1300 hours, but it is considered incorrect to use both 24-hour time and am/pm designations. – Vynce Feb 24 at 20:40
A self-admitted stolen answer should not be the accepted answer, @Ben. – Xynariz Feb 24 at 23:18

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