Anyone smarter than me help with this maths question?

[Mel_P]

Surely brackets make no difference as all subtractions. Would be different if multiply or divide operations?

 

[Rai200]

Me neither. Been going through every possible permutation in an equation solver and can't get it.

6-(5-4)-(4-3) would also work without changing the subtractions, but you need to add another number.

It's either impossible or we are all idiots. 50/50 really.

 

[Mr C]

I remember once upon a time when doing Matrix algebra they used to throw in impossible questions (like asking to add or subtract matrices of different dimensions).

In those cases the correct answer was "No, it can't be done", is this one of those ones?

 

[Hawk Tuah]

It's just question d. He's already got all the rest.

 

[Hades]

Surely brackets make no difference as all subtractions. Would be different if multiply or divide operations?

Brackets can be used to multiply. e.g. 2(4) is the same as 2x4.

 

[Demon]

That's 8.

I replied too early.. mid googling and was revelling in my own stupidity and hit post by mistake..

 

[throwaway4372]

I've been using Wolfram Alpha to try a load of combinations quickly.

Even considering negative multiplication, I'm not finding the answer, thinking the teacher made a mistake.

Considering the others are very easy, I don't think this level would be that tricky.

Here's the link if you want to try it, maybe someone else will luck out, or maybe you'll all just waste time doing the same thing I already did.

6-(5(-4))(-3) - Wolfram|Alpha

Wolfram|Alpha brings expert-level knowledge and capabilities to the broadest possible range of people—spanning all professions and education levels.

www.wolframalpha.com

I'll also point out that all the equations are valid with no brackets because they all resolve to either true or false

 

[Mel_P]

Brackets can be used to multiply. e.g. 2(4) is the same as 2x4.

Yes - but 5*3-4 = (5*3)-4 = 15-4 = 11
NOT 5*-1 = -5

 

[chroniclard]

Trick question!

 

[Baldbloke]

My maths is rusty. Very rusty. I can't see that being possible. Not with just using brackets. And possibly not even proveable without some serious mathematical jiggery pokery.
Must be a typo, surely?

 

[touch]

Surely brackets make no difference as all subtractions. Would be different if multiply or divide operations?

You can change the order the subtractions happen by adding brackets.
Eg.
3-2-1=0
3-(2-1)=2

 

[Demon]

At least putting the following in Wolfram Alpha gives 4

6(-)5-(4-3)=4

Yes, that's cheating, but I suspect the question is broken.. surely you should get merit marks for bucking the system

 

[D.P.]

6-(5-(4-3))=2
saw the sheet of questions and answered f

 

[Chuk_Chuk]

At least putting the following in Wolfram Alpha gives 4

6(-)5-(4-3)=4

Yes, that's cheating, but I suspect the question is broken.. surely you should get merit marks for bucking the system

It ignores the 6 for some reason

 

[div0]

At least putting the following in Wolfram Alpha gives 4

6(-)5-(4-3)=4

Yes, that's cheating, but I suspect the question is broken.. surely you should get merit marks for bucking the system

I don't even follow what (-) does to make that 'work'.

 

[Chuk_Chuk]

I don't even follow what (-) does to make that 'work'.

Maybe it reads (-) as 0.

 

[Thekwango]

If the op doesn’t march into the school tomorrow and falcon punch the teacher I will not be happy.

 

[Demon]

I don't even follow what (-) does to make that 'work'.

It just breaks the WA interpreter..

6(-)5-(4-3) is interpreted as 5-(4-3)

6(-)5-(4-3) - Wolfram|Alpha

Wolfram|Alpha brings expert-level knowledge and capabilities to the broadest possible range of people—spanning all professions and education levels.

www.wolframalpha.com

 

[D.P.]

This is why we can never hire good engineers

 

[Mel_P]

The only way I get 4 from 6, 5, 4, 3 is :

6+5 = 11
-4-3 = -7
11-7 = 4

But the 5 is -5 not +5

NB 6-5-4-3 = -6
6-(5-4-3) is 6-5+4+3 = 8
(i think)