Interesting maths problem
 Hightea
 Posts: 3691
 Joined: 16 Apr 2015, 02:18
 Location: NY state
Re: Interesting maths problem
oh brother 5! is 120
that's why I typically stay out of these silly things.
sorry it should have been: Yet, amazingly, the correct answer is 5!.
otherwise it just sounds that you are screaming the answer is 5.
that's why I typically stay out of these silly things.
sorry it should have been: Yet, amazingly, the correct answer is 5!.
otherwise it just sounds that you are screaming the answer is 5.
 C
 Robust
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 Joined: 22 Jul 2003, 19:06
Re: Interesting maths problem
Sorry, I am late to the party:
Correct and 120 = 5! = 5x4x3x2x1
There are no tricks in mathematics
When there are no brackets and with operations of different 'weight' multiplication/divison overrides addition/subtraction
.
Positive Passion wrote:Surely one has to apply BIDMAS or whatever you call it, so you have
220 x .0.5 = 110.
Then
230  110 = 120.
If the answer really is 5 there's some other trick.
Correct and 120 = 5! = 5x4x3x2x1
There are no tricks in mathematics
When there are no brackets and with operations of different 'weight' multiplication/divison overrides addition/subtraction
.
Last edited by C on 06 Jan 2022, 20:01, edited 2 times in total.
C wrote:Just blank the fucquewit
 C
 Robust
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Re: Interesting maths problem
Positive Passion wrote:You to be working with at least base 6, because otherwise you couldn't have 0.5.
If we were working in base 6  what would 0.5 represent in base 10...?
It obviously wouldn't be a half...
.
C wrote:Just blank the fucquewit
 Rorschach
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 Joined: 02 Jun 2008, 12:43
 Location: The north side of my town faces east, and the east faces south
Re: Interesting maths problem
Hightea wrote:otherwise it just sounds that you are screaming the answer is 5.
That was kind of the point.
Bugger off.

 Posts: 2013
 Joined: 05 Jul 2017, 23:05
Re: Interesting maths problem
C wrote:Positive Passion wrote:You to be working with at least base 6, because otherwise you couldn't have 0.5.
If we were working in base 6  what would 0.5 represent in base 10...?
It obviously wouldn't be a half...
.
5/6, which is about 83%, or 0.83 and change
 souphound
 World Class Ignoramus
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 Location: Tralfamadore, with Montana Wildhack
Re: Interesting maths problem
C wrote:Positive Passion wrote:You to be working with at least base 6, because otherwise you couldn't have 0.5.
If we were working in base 6  what would 0.5 represent in base 10...?
It obviously wouldn't be a half...
.
0.83333333333333333333333333333333333333333333333333333333333333..........?
Footy wrote:Last week, I discovered that the cordless drill I bought about 5 years ago is, in fact, a cordless screwdiver.
 souphound
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Re: Interesting maths problem
And you may note that a "3" is really only the right half of an "8".
Footy wrote:Last week, I discovered that the cordless drill I bought about 5 years ago is, in fact, a cordless screwdiver.
 Rorschach
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 Joined: 02 Jun 2008, 12:43
 Location: The north side of my town faces east, and the east faces south
Re: Interesting maths problem
souphound wrote:And you may note that a "3" is really only the right half of an "8".
Bugger off.
 souphound
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Re: Interesting maths problem
Rorschach wrote:souphound wrote:And you may note that a "3" is really only the right half of an "8".
You can use the "!" to chop down the "8" if you want.
Footy wrote:Last week, I discovered that the cordless drill I bought about 5 years ago is, in fact, a cordless screwdiver.

 Posts: 2013
 Joined: 05 Jul 2017, 23:05
Re: Interesting maths problem
Rorschach wrote:souphound wrote:And you may note that a "3" is really only the right half of an "8".
 C
 Robust
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Re: Interesting maths problem
Positive Passion wrote:C wrote:Positive Passion wrote:You to be working with at least base 6, because otherwise you couldn't have 0.5.
If we were working in base 6  what would 0.5 represent in base 10...?
It obviously wouldn't be a half...
.
5/6, which is about 83%, or 0.83 and change
Correct  but how would you explain that....?
.
C wrote:Just blank the fucquewit
 Deebank
 Resonator
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Re: Interesting maths problem
Sometimes it pays to be ignorant.
I've been talking about writing a book  25 years of TEFL  for a few years now. I've got it in me.
Paid anghofio fod dy galon yn y chwyldro
Paid anghofio fod dy galon yn y chwyldro
 C
 Robust
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Re: Interesting maths problem
Positive Passion wrote:C wrote:Positive Passion wrote:You to be working with at least base 6, because otherwise you couldn't have 0.5.
If we were working in base 6  what would 0.5 represent in base 10...?
It obviously wouldn't be a half...
.
5/6, which is about 83%, or 0.83 and change
The 5/6 is correct but in base 6 does that equate to 0.83...?
Are you not applying base 10 mathematics to a base 6 problem when carrying out the division to change the fraction to a decimal...?
For others:
In base 6 for example 35 can't be read as 'thirtyfive', [we read it as 'threefive'], because in this example 35 is 3 sixes and 5 units which equals 23 (base 10).
Questions for those interested
23 (base 4) + 33 (base 4)
621 (base 7)  155 (base 7)
Incidentally, when I was at school questions like the above we were doing when I was 9 years old. All kids did it because, in the UK, we had systems that did not use the denary/decimal system
Different number bases were part of the primary curriculum
12 pence = 1 shilling
20 shillings = £1
12 inches = 1 foot
3 feet = I yard
16 ounces = 1 pound
112 pounds = 1 hundredweight
8 furlongs = 1 mile
.
C wrote:Just blank the fucquewit

 Posts: 2013
 Joined: 05 Jul 2017, 23:05
Re: Interesting maths problem
C wrote:Positive Passion wrote:C wrote:
If we were working in base 6  what would 0.5 represent in base 10...?
It obviously wouldn't be a half...
.
5/6, which is about 83%, or 0.83 and change
The 5/6 is correct but in base 6 does that equate to 0.83...?
Are you not applying base 10 mathematics to a base 6 problem when carrying out the division to change the fraction to a decimal...?
You asked what the base 10 equivalent of 0.5 in base 6 was.
In base 6, 5/6 would be 0.5.
It is about recognising place value.
Last edited by Positive Passion on 07 Jan 2022, 13:58, edited 1 time in total.
 souphound
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Re: Interesting maths problem
C wrote:Positive Passion wrote:C wrote:
Incidentally, when I was at school questions like the above we were doing when I was 9 years old. All kids did it because, in the UK, we had systems that did not use the denary/decimal system
.
Reading this, I infer that when you turned 10, everything went to decimal?
Sorry. Carry on.
Footy wrote:Last week, I discovered that the cordless drill I bought about 5 years ago is, in fact, a cordless screwdiver.
 C
 Robust
 Posts: 67071
 Joined: 22 Jul 2003, 19:06
Re: Interesting maths problem
Positive Passion wrote:C wrote:Positive Passion wrote:
5/6, which is about 83%, or 0.83 and change
The 5/6 is correct but in base 6 does that equate to 0.83...?
Are you not applying base 10 mathematics to a base 6 problem when carrying out the division to change the fraction to a decimal...?
You asked what the base 10 equivalent of 0.5 in base 6 was.
In base 6, 5/6 would be 0.5.
It is about recognising place value.
Absolutely correct. It was the 0.8333... bit I was highlighting
.
C wrote:Just blank the fucquewit
 C
 Robust
 Posts: 67071
 Joined: 22 Jul 2003, 19:06
Re: Interesting maths problem
souphound wrote:C wrote:Positive Passion wrote:
Reading this, I infer that when you turned 10, everything went to decimal?
Sorry. Carry on.
.
C wrote:Just blank the fucquewit
 Darkness_Fish
 Posts: 7518
 Joined: 27 Jul 2015, 09:58
Re: Interesting maths problem
There are 10 kinds of people.
Those who understand hexadecimal and those who don't understand hexadecimal. The friends of people who understand hexadecimal, but don't themselves understand hexadecimal. The friends of people who do understand hexadecimal, and also understand hexadecimal. Then there are those who wish they'd chosen a smaller base before starting a joke. Then the friends of those who wish...
Those who understand hexadecimal and those who don't understand hexadecimal. The friends of people who understand hexadecimal, but don't themselves understand hexadecimal. The friends of people who do understand hexadecimal, and also understand hexadecimal. Then there are those who wish they'd chosen a smaller base before starting a joke. Then the friends of those who wish...
Like fastmoving clouds casting shadows against a hillside, the melodyloop shuddered with a sense of the sublime, the awful unknowable majesty of the world.
 Rorschach
 Posts: 3744
 Joined: 02 Jun 2008, 12:43
 Location: The north side of my town faces east, and the east faces south
Re: Interesting maths problem
Darkness_Fish wrote:...Then there are those who wish they'd chosen a smaller base before starting a joke ...
Maybe try base 3 next time. (Binary's been done to death.)
Bugger off.
 Charlie O.
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Re: Interesting maths problem
(Lehrer's "day job" at the time [1965]. and for many years before and after, was lecturing on mathematics at MIT, Harvard, and others of that ilk.)