Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

in reality, all of this has been a total load of old bollocks
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C
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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby C » 19 Jun 2018, 11:54

Positive Passion wrote:
C wrote:63+36

= (60+3)+(30+6)

= 66 +33

= 11(6+3)

So the general case:

ab + ba (where a and b are integer digits)

= (10a +b) + (10b + a)

= 11a + 11b

= 11(a+b)

which will always be a multiple of 11 irrespective of digit values




.


But that is just what I said!


Exactly!





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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby Deebank » 20 Jun 2018, 08:03

22/7 is pi!!!!!!
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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby never/ever » 20 Jun 2018, 09:59

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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby Deebank » 20 Jun 2018, 10:09

Pansy Puff wrote:
Deebank wrote:22/7 is pi!!!!!!

No it isn't!!


That's what I was told by my teachers!

Bloody teachers :x
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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby Tom Waits For No One » 20 Jun 2018, 11:01

Those that were born in 45 were 33 in 78





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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby C » 20 Jun 2018, 18:26

Pansy Puff wrote:
Deebank wrote:22/7 is pi!!!!!!

No it isn't!!


A number that cannot be expressed as a fraction is called an irrational number. Pi is one of these numbers.

An irrational number is a number that does not recur in a decimal pattern – like pi where the decimal places go on forever in no set order or pattern

To approximate we use values of pi which include 22/7, 3.1, 3.14, 3.1412 depending on the level of accuracy required.

So an approximate value of pi 22/7, as stated by your teacher, is correct

It follows that a number that can be expressed as a fraction recurs in a decimal pattern and is called a rational number

Eg 0.333..= 1/3
0.121212…= 12/99
0.173173173... = 173/999
0.166666666… = 1/6

This includes terminating decimals that ‘stop’
Eg 0.1 = 0.10000000… = 1/10

For the record an integer (whole number including zero) is a rational number because they can also be expressed as a fraction
Eg 6 = 6/1
5 = 30/6
0 = 0/9





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Last edited by C on 20 Jun 2018, 18:40, edited 2 times in total.
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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby NMB » 20 Jun 2018, 23:04

Pansy Puff wrote:And the set of rational numbers is the same size as the set of integers!


Only in the sense that they’re both infinite. Else to disprove it, all integers are rational. 1/2 is rational but not integer. So number of rationals must be at least number of integers plus 1.
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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby Teabag » 21 Jun 2018, 05:42

Well, Jimi said if six was nine he didn't mind, and that's good enough for me.
I could be wrong. I usually am.

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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby C » 21 Jun 2018, 07:41

Teabag wrote:Well, Jimi said if six was nine he didn't mind, and that's good enough for me.


Neil, my dear dear friend.

thank you for popping in




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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby C » 21 Jun 2018, 07:45

Pansy Puff wrote:They are both countable and can be put in a one to one correspondence so they are the same size of infinity. But the set of real numbers is uncountable and hence a larger infinity.


Oh no!

I can feel Hilbert's Hotel paradox looming.....!!

https://en.wikipedia.org/wiki/Hilbert%2 ... rand_Hotel






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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby Positive Passion » 21 Jun 2018, 17:46

Pansy Puff wrote:
NMB wrote:
Pansy Puff wrote:And the set of rational numbers is the same size as the set of integers!


Only in the sense that they’re both infinite. Else to disprove it, all integers are rational. 1/2 is rational but not integer. So number of rationals must be at least number of integers plus 1.

An example to show the problem with your disproof.

The set S ={1, 2, 3,...} is infinite in size. If I remove all the odd numbers then surely I have a set of numbes that is smaller,
E ={2, 4, 6, ...} .After all, I have removed every other number.

But if I take set S and double every number then I get the same set of numbers E ={2, 4, 6...} But if I doubled every number the set must be the same size as S.

So I have shown that S and E are the same size, and that S is "twice as big" as E.


Huh? Surely half infinity is still infinity. As is twice inifinity.

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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby NMB » 21 Jun 2018, 23:26

Pansy Puff wrote:
Positive Passion wrote:
Pansy Puff wrote:An example to show the problem with your disproof.

The set S ={1, 2, 3,...} is infinite in size. If I remove all the odd numbers then surely I have a set of numbes that is smaller,
E ={2, 4, 6, ...} .After all, I have removed every other number.

But if I take set S and double every number then I get the same set of numbers E ={2, 4, 6...} But if I doubled every number the set must be the same size as S.

So I have shown that S and E are the same size, and that S is "twice as big" as E.


Huh? Surely half infinity is still infinity. As is twice inifinity.

Which infinity are you talking about? Some infinities are bigger than others.

https://en.wikipedia.org/wiki/Aleph_number


So my infinity plus one can be bigger than your infinity and my disproof stands.
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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby C » 24 Jun 2018, 13:31

7 is three-and-a-half times greater than 2

The product of 2 and 3.5 is 7

7 divided by 2 is 3.5

2 lots of 3.5 is 7








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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby C » 27 Jun 2018, 15:37

7 is odd

2 is even






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