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Weird Maths (6 / 1.5)


SiRaLeX

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20/1=20

20/2=10

 

so 20/1.5=15...?

 

(15 seconds later)okay, I just found that through the calculator the answer is wrong and I was literally confident it's right!!!(wtf)

 

Math is always weird for me. I just never understand its logic. But I do know 1 and 1 is 2.

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20/1=20

20/2=10

 

so 20/1.5=15...?

 

(15 seconds later)okay, I just found that through the calculator the answer is wrong and I was literally confident it's right!!!(wtf)

 

Math is always weird for me. I just never understand its logic. But I do know 1 and 1 is 2.

Exactly! For some weird reason the answer is 13.3333333 (as I have proven with my lengthy post and drawing above). From a logical standpoint this does not make any sense. However the calculator says it is so, then it is so (I never question the calculator).

 

I really wonder what...

 

6 / X = 4.5

would be?

 

Let's find out!

6 / X      = 4.5           | * X
6          = 4.5X          | * 2
12         = 9X            | / 9
12 / 9     = X
4 / 3      = X
1.3333333  = X

 

Note that there's actually a period on 1.3 (as if this wasn't confusing enough).  :laugh: 

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Okay, your claim is:

 

if  c                      c                            c          x + y

    ---  = x    and    ---  = y,      then,  -------  =  ------.  Let's see what can we get here:

    u                      v                          u+v          2

                                                          ----

                                                            2

take u != -v.

 

since if a = c and b = d implies that a+b = c+d, then:

 

  c      c                          1    (  c        c  )        x+y

---  + ---  =  x+y , then  --- * ( ----  + ---- )  =  ----

  u      v                          2    (  u        v )          2

 

then    c            c        c                        c          2c

        ------  =  -----  + -----  .      But    ------  =  -------

        u+v        2u      2v                      u+v      u+v

          ----                                              ----

          2                                                2

 

              2c          c        c              4c          c        c

then      ------  =  ----  + -----,        -------  =  ----  + -----

              u+v          2u      2v            u+v        u        v

 

And that is only true when u = v.

 

[edit]: I just noticed that he was dividing (u+v)/2, not the entire number.

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20/1=20

20/2=10

 

so 20/1.5=15...?

 

(15 seconds later)okay, I just found that through the calculator the answer is wrong and I was literally confident it's right!!!(wtf)

 

Math is always weird for me. I just never understand its logic. But I do know 1 and 1 is 2.

Exactly! For some weird reason the answer is 13.3333333 (as I have proven with my lengthy post and drawing above). From a logical standpoint this does not make any sense. However the calculator says it is so, then it is so (I never question the calculator).

 

I really wonder what...

 

6 / X = 4.5

would be?

 

Let's find out!

6 / X      = 4.5           | * X
6          = 4.5X          | * 2
12         = 9X            | / 9
12 / 9     = X
4 / 3      = X
1.3333333  = X

 

Note that there's actually a period on 1.3 (as if this wasn't confusing enough).  :laugh: 

Ok, that last post, made me laugh, sorry for that.

Really sorry, but it's just... just...

...

Please tell me you where joking. You thought was logical at first?

 

But then again. Could you please tell me why you find it logical at first? Just because it would fit in a certain list?

I asked people over here that do not understand "the why and how" either regarding this. And of some, I expected them to be... smarter then me.

I am starting to find this fascinating, how some people do not understand even simple math just like how most animals don't understand their own mirror image.

At first I thought you were an idiot and/or just trolling us. But now I see that it is... very common indeed, that some people simply do not understand.

 

May I ask, how do you feel about these?

- When sound is twice as hard, we only add 3 dB. So 33 dB is twice as hard than 30 dB.

- When an object orbiting the sun takes 1 year. And object at twice the distance, weighs towards the sun only 14th, yet takes 2.8 years to orbit.

- When you double your distance of an object that makes sound, the dB is 6.

 

- 80 degrees Celcius (or Farhenheit) is not twice 40 degrees Celcius (or Farhenheit).

- 0 degrees Celcius is not absolute cold, but actually 273 Kelvin.

- 0 Kelvin is practically not possible.

- If you add 10 degrees Celcius (not Farhenheit) or 10 Kelvin, most reaction times go twice as fast.

 

- When you add 1 kg salt to 1 Liter water, you get 1,3 Liter salt water. With a density of about 1.54 kg per Liter.

- When you completely burn 1 kg carbon (black/grey and falls down), you get 4.2 kg carbondioxide (that floats away).

- When you completely burn 1 kg hydrogen gas (that floats away) you get a pool of water that weighs 9 kg.

 

 

 

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Now now people lets cool this a little bit.

X3M stop getting frustrated at people who aren't so knowledgable in Mathematics. Not everyone can just understand it.

 

When sound is twice as hard, we only add 3 dB. So 33 dB is twice as hard than 30 dB.

I don't know how the units of Sound actually work so I'm not sure. Also is the word you were looking for "loud"?

 

When an object orbiting the sun takes 1 year. And object at twice the distance, takes 4 years.

Keplers Law (Relating to Newtons Law of Gravitation) says that T2 (Time Period) is proportional to R3 (Radius of Orbit), so in reality it takes about 2.8 times longer.

 

- 80 degrees Celcius (or Farhenheit) is not twice 40 degrees Celcius (or Farhenheit).

- 0 degrees Celcius is not absolute cold, but actually 273 Kelvin.

- 0 Kelvin is practically not possible.

- If you add 10 degrees Celcius (not Farhenheit) or 10 Kelvin, most reaction times go twice as fast.

Celcius and Kelvin are the same scale, but Celcius doesn't start from Zero (But Kelvin Does, hence absolute Zero = 0oK)

I assume you're talking about a Chemical Reaction? If so that relates to the activation energy of the molecules required to actually start the reaction. Higher Temp -> More Molecules able to react

 

When you add 1 kg salt to 1 Liter water, you get 1,3 Liter salt water. With a density of about 1.54 kg per Liter.

Salt has a volume and Density too.

 

- When you completely burn 1 kg carbon (black/grey and falls down), you get 4.2 kg carbondioxide (that floats away).

- When you completely burn 1 kg hydrogen gas (that floats away) you get a pool of water that weighs 9 kg.

Gases have mass.

 

Theres clear logic to most of Science and Maths, but bashing people because they don't get it isn't going to help anybody.

 

In fact I just started the Quantum Mechanics part of my degree and its fairly safe to say that some of the logic within that is rather backwards.

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Now now people lets cool this a little bit.

X3M stop getting frustrated at people who aren't so knowledgable in Mathematics. Not everyone can just understand it.

 

I am not frustrated. I said I get it now. I asked around and there are plenty of people, which surprised me at first.

 

I am curious as of how people deal with not knowing. This helps me in my study of the human mind.

And thanks for answering some of the questions.

 

You are right about the Keplers Law. Please allow me to change it.

 

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The problem with Monty hall is that it is not really a problem - it is a fraud.

 

It's based on the fact that a 50 % chance is better than a 33 % chance - which is correct, but the whole set up is flawed.

 

1. You pick a door with a 33 % winning chance.

2. The host removes a door - suddenly making your choice a 50 % winning chance (obviously).

3. Now you have the chance of switching the door. They want to make you believe that switching is beneficial because if you switch you have a 50 % winning chance as opposed to your original 33 %. This is the fallacy - because your chance of winning already is 50 % since the last step.

 

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Actually, math people know the chance is even 66,7% now, instead of 50%. That is why it is such a good showcase for those who just started doing math tricks.

 

The key with the Monty Hall problem is that each door starts with 1/3th of a chance of winning that car.

After the player has chosen a door.

The show host can only open a door that does not contain the car, nor the chosen door by the player.

 

This means that 2 times 1/3th, is now combined into only 1 door that was not chosen.

Thus the door that the player had chosen at first, is and remains 1/3th. And the other remaining door has now 2/3th of a chance.

 

If you write down each possibility on paper of what is happening, you can see the same result. If the player changes the choice of the door. The player wins 2 times out of 3. If the player does not change the choice of the door, the player wins only 1 time out of 3.

 

There are variations to this problem, with more doors. But also with more doors being opened by the host of the show.

 

If there are 100 doors. And the player may chose one. Then the host opens all the other doors, except for one other door. Is the chance still 50-50? I know that the chance that it was the first choice is 1%. While if it is the remaining door, 99%.

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The problem with Monty hall is that it is not really a problem - it is a fraud.

 

It's based on the fact that a 50 % chance is better than a 33 % chance - which is correct, but the whole set up is flawed.

 

1. You pick a door with a 33 % winning chance.

2. The host removes a door - suddenly making your choice a 50 % winning chance (obviously).

3. Now you have the chance of switching the door. They want to make you believe that switching is beneficial because if you switch you have a 50 % winning chance as opposed to your original 33 %. This is the fallacy - because your chance of winning already is 50 % since the last step.

 

 

Did you actually read the page?

By simply looking at the scenario you can assume its only a 50/50 (Like many), but when they did the maths and go through it, it works out to be 2/3, not 50/50. Its weird but the underlying calculations shows that it actually makes sense.

 

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If there are 100 doors. And the player may chose one. Then the host opens all the other doors, except for one other door. Is the chance still 50-50? I know that the chance that it was the first choice is 1%. While if it is the remaining door, 99%.

Very good explanation. You should be a teacher!  :yuri:

 

And no, I didn't actually read the wiki page - only skimmed through it (not that I'd be able to understand it all).  :)  Still, I did not believe it. What X3M says, however, makes full sense. But this is not about 100 doors - only about 3 doors and no, I wouldn't switch the door!  ;)

 

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If there are 100 doors. And the player may chose one. Then the host opens all the other doors, except for one other door. Is the chance still 50-50? I know that the chance that it was the first choice is 1%. While if it is the remaining door, 99%.

Very good explanation. You should be a teacher!  :yuri:

 

And no, I didn't actually read the wiki page - only skimmed through it (not that I'd be able to understand it all).  :)  Still, I did not believe it. What X3M says, however, makes full sense. But this is not about 100 doors - only about 3 doors and no, I wouldn't switch the door!  ;)

 

You perhaps may not trust the math calculations behind it, but I think that if you write a very simple simulation of this problem, then you will convince yourself.

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You perhaps may not trust the math calculations behind it, but I think that if you write a very simple simulation of this problem, then you will convince yourself.

You mean, like a program with random numbers?

 

I may do that on the weekend and report my findings.  ;)

 

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May I ask, how do you feel about these?

Sure.

 

 

- When sound is twice as hard, we only add 3 dB. So 33 dB is twice as hard than 30 dB.

Confusing because it's non-linear! That also means we can never have complete silence because something can only be half as loud as something else - which is bollocks. I guarantee that if you build a bunker 100 meters under the surface with 10 meter thick walls you should technically have 0 dB inside.

 

 

- When an object orbiting the sun takes 1 year. And object at twice the distance, weighs towards the sun only 14th, yet takes 2.8 years to orbit.

I don't get that. What does weight have to do with how long it takes object x1 to orbit object y in comparison how long it takes object x2 to orbit object y?

 

 

- When you double your distance of an object that makes sound, the dB is 6.

Weird. Does not make sense to me.

 

 

- 80 degrees Celcius (or Farhenheit) is not twice 40 degrees Celcius (or Farhenheit).

I agree with that. Temperatures are non-linear. I had an argument about this with a friend once. I claimed that it takes a lot higher heat (= and thus more energy) to heat up something that is 30 °C to 35 °C or 1000 °C to 1005 °C than it takes to heat up something that is 20 °C to 25 °C. Although the delta T is the same, namely 5 K and my physics studies would like to tell me otherwise. I still believe I'm right.

 

You can't compare a feather to a steel ball in free fall. This is the real world - try it yourself! Stupid formulas telling me the gravitational force is 9.81 m/s² and the speed in free fall only depends on mass and height are just that, stupid.

 

Honestly, I've got exactly nothing out of my physics studies that I can put to use in my life. If anything, studying physics will make you dumber. Just ignore it - you'll be fine (like me and just use your brain and learn to handle a calculator). Physics on a basic level is just maths disguised with some bullshit formulas that have at best 80 % accuracy and 0 % real life relevance. You're better off with maths alone (I can do maths, even though this topic might suggest otherwise).

 

 

- 0 degrees Celcius is not absolute cold, but actually 273 Kelvin.

0 °C is the freezing point of water while 100 °C is the boiling point. I'm cool with that. Seems natural to me (I'm from mainland, Europe).

 

 

- 0 Kelvin is practically not possible.

That's weird. I know that atoms move around and shit thus creating some heat. But what about in a vacuum?

 

 

- If you add 10 degrees Celcius (not Farhenheit) or 10 Kelvin, most reaction times go twice as fast.

Well, my reaction time surely won't go faster when my body temperature is at 47 °C as opposed to 37 °C because I'd be dead by then.

 

 

- When you add 1 kg salt to 1 Liter water, you get 1,3 Liter salt water. With a density of about 1.54 kg per Liter.

Salt has higher density than water (more weight by volume). Liters are a unit used to describe volume - not weight. This is much like saying 1 KG feathers is the same weight as 1 KG of rocks. Logical, but some people will still think that the rocks are heavier. Mass does not equal volume, at all.

 

 

- When you completely burn 1 kg carbon (black/grey and falls down), you get 4.2 kg carbondioxide (that floats away).

Obviously this requires 3.2 KG of oxygen to be present wherever you decide to burn that carbon.

 

 

- When you completely burn 1 kg hydrogen gas (that floats away) you get a pool of water that weighs 9 kg.

That requires 8 KG of oxygen to be present wherever you chose to burn that hydrogen gas.

 

 

I hope I satisfied your curiosity regarding my Dyscalculia.  :heady:

 

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SiRaLex: You should check this tool:

http://www.wolframalpha.com/

 

you can plot graphs, derivate functions, integrate, solve linear systems, etc.

Do you have premium? I'm considering getting premium, because they show solving routes (which they don't in basic).

 

Just wondering if it is worth it?

 

I have Mathematica, it do all those things the premium do and more. The solver routes works very well with Integrals (with limits they only use L'Hospital rule everywhere, ruining the state of art).

I got it free from where I study, I don't know how expensive it really is.

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No, never used. You ?

Hell, yeah. I regularly jab my thigh, I love it! Was just wondering because you looked quite good on your S-T avatar (if that's indeed you).

 

 

Just went to McDonald's, ordered and paid for 4 cheeseburgers, got 5, l0l, idiots!

thigh.jpg.83e453784acc072e54242e448076b1a3.jpg

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