This is so easy to get right...or wrong...

[srw]

There is no answer.

I teach GCSE Maths and I would hope any of my students could tell you that. Talk about BODMAS (or BIDMAS) is irrelevant.

The only thing the symbols can possibly represent is either the things themselves (burgers, chips or cola) or the price thereof (5, 2 and 10, respectively, in some unspecified currency - let's say £ for the sake of argument).

Neither
chips x cola
or
£2 x £5

makes sense in any known universe.

Not true. In this puzzle a picture of a burger has exactly the function of the letter x in a piece of more conventional algebra. Try it out on your class - the best mathematicians will come up with the answer 25 until you point out the two packets of chips, which function exactly as 2z would in more conventional algebra.

The notion of using letters to represent numbers is just conventional. I think you'd be right if the puzzle included currency symbols, but it doesn't.

 

[Oxo]

52 for winjim's puzzle.

 

[srw]

This one:

That is crap. But also quite interesting. We have a convention that + means addition - a convention which is relatively recent historically (16th century if memory serves). This puzzle uses the convention that + means something different.

 

[Scoosh]

Spoiler: The Definitive Answer for all of them

42

 

[swee'pea99]

the best mathematicians will come up with the answer 25

Eh? I had thought that having got over my initial failures - to distinguish the one chips/two chips, and to spot the x rather than + symbol - followed up by taking on board the requirement to multiply before adding (don't know why, but I'm a trusting soul) - I arrived at what I'd assumed was the correct answer: to whit, 15 - ie, 5 + (1 x 10). Now you're telling me it's 25? Now what have I got wrong?

 

[Deleted member 26715]

Not true. In this puzzle a picture of a burger has exactly the function of the letter x in a piece of more conventional algebra.

If that were true using that convention as the 2nd bag of fries is set up higher it is indicating that it is to the power of, therefore that line reads,

Burger + fries to the power of fries + fries to the power of fries = 9

 

[DaveReading]

The notion of using letters to represent numbers is just conventional. I think you'd be right if the puzzle included currency symbols, but it doesn't.

Nope, either way round it doesn't make sense. You can only sensibly multiply two numbers together if either at least one of them is non-dimensional, or they represent two physical dimensions whose product also has a physical representation (e.g.length x breadth of a rectangle = area).

There may be a universe where burger-chips exist, but we haven't discovered it yet.

 

[Oxo]

There may be a universe where burger-chips exist, but we haven't discovered it yet.

Tell that to my daughter next time she is making tea.

 

[User482]

It's a good job that no-one is taking this too seriously.

 

[User6179]

It's a good job that no-one is taking this too seriously.

It will be moved to S,C&P before the day is out .

 

[srw]

Eh? I had thought that having got over my initial failures - to distinguish the one chips/two chips, and to spot the x rather than + symbol - followed up by taking on board the requirement to multiply before adding (don't know why, but I'm a trusting soul) - I arrived at what I'd assumed was the correct answer: to whit, 15 - ie, 5 + (1 x 10). Now you're telling me it's 25? Now what have I got wrong?

In my mind, 25 is a more interesting answer mathematically, even if it's not what the question-setter intended. And that's because maths is all about abstraction, and when you see a picture of "some chips" a mathematical mind* will abstract to "chips"

Nope, either way round it doesn't make sense. You can only sensibly multiply two numbers together if either at least one of them is non-dimensional, or they represent two physical dimensions whose product also has a physical representation (e.g.length x breadth of a rectangle = area).

There may be a universe where burger-chips exist, but we haven't discovered it yet.

If the puzzle had been written:
x + x + x = 30
x + y + y = 20
y + 2z + 2z = 9
you wouldn't quibble. But the use of "x" to represent an unknown mathematical quantity is a convention, invented a couple of hundred years ago. The convention of this puzzle is:
x <-> picture of drink
y <-> picture of burger
z <-> picture of box of chips.

Again - it's about abstraction. The puzzle-setter has decided to use pictures where normal mathematical convention is to use letters from the end of the alphabet. And at least some of your class will recognise that.

If that were true using that convention as the 2nd bag of fries is set up higher it is indicating that it is to the power of, therefore that line reads,

Burger + fries to the power of fries + fries to the power of fries = 9

I like that one - although the convention isn't usually to overlap powers. And the maths is much more difficult.

It's a good job that no-one is taking this too seriously.

I know - what more fun can anyone have on a dismal grey December day than playing about with maths?!


*OK, OK. My mathematical mind.

 

[Starchivore]

ah balls I fell into the trap

 

[screenman]

I thought the answer was obesity.

 

[wormo]

70

 

[nickyboy]

If that were true using that convention as the 2nd bag of fries is set up higher it is indicating that it is to the power of, therefore that line reads,

Burger + fries to the power of fries + fries to the power of fries = 9

Fries squared....summat like these?

They're so waffly versatile