Poll: 6÷2(1+2)

[Castiel]

I know you have sour grapes because you (a) fell over yourself and (b) were shown to be wrong, but please don't troll for the sake of it.

Why should I have sour grapes? I'm not the one having a stroke over an ambiguous formula, you are, also I wasn't wrong as I voted 9, while recognising the ambiguity, something your ego will not allow you to do

as my calculator demonstrated:

This is what I get:

6÷2(1+2)=1

or

or

6/2(1+2)=9

lol

 

[semi-pro waster]

At least we could test that.

Also, isn't the answer no? There is no lift if the plane is still.

The answer is yes, it will take off. The wheels and treadmill are essentially a red herring as they're not driving the aircraft to take-off speed, they're there to allow the aeroplane to move forwards under the power of the engines propulsion (either propeller or jet). It's the air moving over/under the wings that generates the lift.

Or maybe it would help to think of the example of a sea-plane, no wheels involved yet it can still propel itself forwards to take off speed.

And in answer to the original question - I'd go with 9 based on BODMAS but I can follow the thought process that gets 1 as well.

 

[Sin_Chase]

9.

From reading the subject and nothing in the thread and having never heard of BODMAS or w/e that is.

 

[dowie]

I don't agree.

I think that you can't make a definition like that. A '÷' or '/' divides. That's it.

It's then up to you as the user to define what divides what by what by using brackets.

Without brackets there is no right or wrong, just perception.

You can though and people already have

÷ is already defined

this is one of the problems with using it - it can be confusing and ordinarily isn't used in mathematics.

If you're going to create a calculator or spreadsheet program you'll have to define ÷ or '/' one way or another

 

[muon]

The answer is yes, it will take off. The wheels and treadmill are essentially a red herring as they're not driving the aircraft to take-off speed, they're there to allow the aeroplane to move forwards under the power of the engines propulsion (either propeller or jet). It's the air moving over/under the wings that generates the lift.

My basic understanding is just the lift aspect and so I poorly applied it. Engines provide direct forward thrust (moving air) as you said, and if you're on a conveyor belt, the wheels will simply spin faster and you will still move forwards??

That the jist of it?

 

[sk82jack]

You can though and people already have

÷ is already defined

this is one of the problems with using it - it can be confusing and ordinarily isn't used in mathematics.

If you're going to create a calculator or spreadsheet program you'll have to define ÷ or '/' one way or another

But we're not talking about implementing any definitions into a spreadsheet or calculator. We are talking about real life maths.

They may be defined by a certain company or by certain people but they are not internationally or globally defined, as different calculators produce different answers from the same equation.

 

[Rroff]

And in answer to the original question - I'd go with 9 based on BODMAS but I can follow the thought process that gets 1 as well.

I can follow the process of thought that gets to 1 but its flawed and the equation is in no way ambiguous - there is a standard way to handle the equation - putting it into a calculator shows that:

6 divided by 2 times 3 on a calculator comes out as 9 - how else do you do it?

 

[gambitt]

Type it into a calculator and see if you get a singe answer or an error message.

Yes that's right, calculators know the answer to everything. Why don't you try putting 1÷0 into it and posting your 'answer'.

Surprisingly you'll find that someone has defined the symbol '÷' and therefore there is only a single answer. Maybe calculator manufacturers are arrogant LOL

Your solution of 81 has nothing to do with the ÷ sign you keep banging on about, it's to do with the order in which you calculate (left to right etc) but this 'rule' doesn't hold for mathematical axioms.

There isn't anything arrogant about stating something that is correct

"Nothing arrogant about being correct" - PMSL - you should get that printed on a T shirt.

 

[plasmahal]

I don't know why your engineers' brain does that, when you should be thinking beyond GCSE level mathematics and understand the standard order of operations.

parenths, exponents and roots, multiplication and division, addition and subtraction ... going from left to right.

As someone who clearly cannot accept the concept that both answers are correct depending on how you approach the problem, you need to open you mind some more.

I was stating that my interpretation is different to my daughters and therefore we are both right.

When I look at that sum, I put the 6 above the line the rest below the line so then work out the problem below the line first then divide by 6 giving me 1. Likewise, If I apply the rules so many are touting, I get 9.

As the sum is ambiguous, people interpret it in different ways based on their knowledge or logic and arrive at different answers.

You and others who insist that 9 is the only possible answer need to understand the subtleties of ambiguity.

Hope that makes it clearer for you.

 

[Rroff]

No the equation is not ambiguous - using any standard way to interpret an equation there is nothing to indicate 6 over blah - to make it ambiguous your inventing stuff - its like saying the speed limit is ambigous if you read the numbers upside down.

 

[plasmahal]

I can follow the process of thought that gets to 1 but its flawed and the equation is in no way ambiguous - there is a standard way to handle the equation - putting it into a calculator shows that:

6 divided by 2 times 3 on a calculator comes out as 9 - how else do you do it?

2 times 3 = 6

6 divided 6 = 1

See both are right.......

 

[dowie]

Yes that's right, calculators know the answer to everything. Why don't you try putting 1÷0 into it and posting your 'answer'.

You've missed the point again

the symbol ÷ has to be defined

the definition isn't complicated

the equation in the OP isn't complicated

there is only one answer

 

[semi-pro waster]

My basic understanding is just the lift aspect and so I poorly applied it. Engines provide direct forward thrust (moving air) as you said, and if you're on a conveyor belt, the wheels will simply spin faster and you will still move forwards??

That the jist of it?

Pretty much, the wheels are frictionless or near enough in the example so they're going to spin faster to compensate for the effect of the treadmill.

I can follow the process of thought that gets to 1 but its flawed and the equation is in no way ambiguous - there is a standard way to handle the equation - putting it into a calculator shows that:

6 divided by 2 times 3 on a calculator comes out as 9 - how else do you do it?

I'm in agreement about the answer if you're following the standard BODMAS/BOMDAS but if you don't follow that process then it's apparently possible to get other answers.

 

[Pinkribbonscars]

I can follow the process of thought that gets to 1 but its flawed and the equation is in no way ambiguous - there is a standard way to handle the equation - putting it into a calculator shows that:

6 divided by 2 times 3 on a calculator comes out as 9 - how else do you do it?

There is a standard way for each calculator of course, because they are programmed, but humans will interpret the equation in multiple ways because it isn't written correctly.

 

[gambitt]

the equation in the OP isn't complicated

there is only one answer

See previous post about closed minded arrogance etc.

 

[Rroff]

2 times 3 = 6

6 divided 6 = 1

See both are right.......

Where in the equation does it tell you to do 2 times 3 on its own? the only bit thats indicated out of order is the 1+2.

 

[sk82jack]

You've missed the point again

the symbol ÷ has to be defined

the definition isn't complicated

the equation in the OP isn't complicated

there is only one answer

Your right that there is only one answer, as to any linear problem, but there are two possible questions.

 

[Rroff]

There is a standard way for each calculator of course, because they are programmed, but humans will interpret the equation in multiple ways because it isn't written correctly.

No its not written correctly, but there is only one correct way in which to correct it using standard rules - or reject it as incorrect - you can't make up another way to correct it.

 

[dowie]

But we're not talking about implementing any definitions into a spreadsheet or calculator. We are talking about real life maths.

÷ isn't generally used in 'real life' maths

we us fractions where the divisor is rather clear

 

[dowie]

See previous post about closed minded arrogance etc.

Its not arrogance - its just a simple expression with an operator that has a standard use. There is only one answer, the operator has a use, the answer is 9.... I can see why some people have trouble understanding, but they're still wrong.