View Full Version : Maths Teaser Adults can't do.


poppet2
05-03-2012, 11:39
This is a sum for primary school children which millions of Adults couldn't get right. Can you?

You have 3 parcels
Parcels A and B together weigh the same as parcel C
The three parcels weigh 800gms altogether
Parcel A weighs 250gms
How much does parcel C weigh?

................................

steve68
05-03-2012, 11:41
400gms......................

hyper
05-03-2012, 11:46
so C is half the weight of the total of 800 = 400
why do we need the weight of A? or am I missing something?

This si the sort of problem displayed at my lad's secondary school, so i don't know why they say its for primary school. Primary school for Oxbridge potentials perhaps? Might have been more sensionalist if they said it was for mums & baby's classes

rubydazzler
05-03-2012, 11:48
400gms......................That can't be right, can it? Because I would have said that as well, and I'm rubbish at maths. And if millions of adults can't get it right, why would we two be any different?

No, it must be more complicated than that. :)

barleycorn
05-03-2012, 11:52
A + B = C and A = 250 so...
(1) B - C = -250

A + B + C = 800 and A = 250 so...
(2) B + C = 550

(2) - (1)
B + C = 550
B - C = -250 -
2C = 800
C = 400
B = 150

jb

truman
05-03-2012, 11:57
A+B+C=800
A+B=C

so C+C=800
C=400

Why do we need to know how much A weighs?

barleycorn
05-03-2012, 12:00
A+B+C=800
A+B=C

so C+C=800
C=400

Why do we need to know how much A weighs?

So that you can waste your doing doing it the long way like I did. D'oh.

jb

steve68
05-03-2012, 12:08
A+B+C=800
A+B=C

so C+C=800
C=400

Why do we need to know how much A weighs?

You don't in my day :o you wouldn't have it would have been.....

You have 3 parcels
Parcels A and B together weigh the same as parcel C
The three parcels weigh 800gms altogether

How much does parcel C weigh?


even then we would have p'd ourselves at how easy that was:hihi:

splodgeyAl
05-03-2012, 12:09
A+B+C=800
A+B=C

so C+C=800
C=400

Why do we need to know how much A weighs?

So that you can waste your doing doing it the long way like I did. D'oh.

jbIndeed. Or maybe the problem with these so-called "elementary maths problems that adults can't do" is that the question is badly written that it confuses people?

alchresearch
05-03-2012, 12:18
Indeed. Or maybe the problem with these so-called "elementary maths problems that adults can't do" is that the question is badly written that it confuses people?

I agree, the weight of parcel A clouded things a little for me. It's a meaningless fact in the equation, but I started to wonder if parcels A and B are the same size and weight.

spooky3
05-03-2012, 12:19
Is this maths or English comprehension?

Phanerothyme
05-03-2012, 12:25
Is this maths or English comprehension?

Both.

Rarely in life do mathematical problems present themselves in algebraic notation.

HeadingNorth
05-03-2012, 13:09
I suspect that this problem has been set with a typographical error. Otherwise it is both ridiculously easy, and has extraneous information is it. The only reason anyone would struggle with it is because they would assume that the blindingly obvious answer must somehow be wrong, since it doesn't require the weight of parcel A to obtain it.

Alcoblog
05-03-2012, 14:07
It's obvious that it would be impossible to work out the answer without knowing what was inside the parcels.
Maybe it would be possible to cut down the weight of parcel 'C' (it may contain some chocolate which could be eaten a bit) to save on the cost of postage?
The only possible way of solving this brain teaser is to take parcels 'B' and 'C' to the Post Office and have them weighed.

rossyrooney
05-03-2012, 14:12
is it 15?.................

alchresearch
05-03-2012, 14:27
Shouldn't the puzzle have been:

You have 3 parcels.

Parcels A and B together weigh the same as parcel C

What time will the postman sneak up to your house and put in a "sorry you weren't in" card through the letterbox without disturbing you because he couldn't be bothered carrying it from the depot?

What are the odds of all parcels being damaged or opened by Royal Mail?

Alien52
05-03-2012, 14:39
is it 15?.................

Well done.Your prize is in the post.

llamatron
05-03-2012, 15:11
Shouldn't the puzzle have been:

You have 3 parcels.

Parcels A and B together weigh the same as parcel C

What time will the postman sneak up to your house and put in a "sorry you weren't in" card through the letterbox without disturbing you because he couldn't be bothered carrying it from the depot?

What are the odds of all parcels being damaged or opened by Royal Mail?

you forgot "lost"

rubydazzler
05-03-2012, 15:13
I suspect that this problem has been set with a typographical error. Otherwise it is both ridiculously easy, and has extraneous information is it. The only reason anyone would struggle with it is because they would assume that the blindingly obvious answer must somehow be wrong, since it doesn't require the weight of parcel A to obtain it.That's what I meant when I posted @ #4

Either that or poppet was lying when she said millions of people got it wrong :)

HTM_1983
05-03-2012, 15:20
I think the idea of knowing parcel A's weight it to throw you slightly and probably why some adults get it wrong as they may think that A and B are the same so therefor would get C's weight wrong. . . . .

WasThatWise
05-03-2012, 15:29
If a plus b weigh the same as c then both a plus b AND c weigh 400gms So if a weighs 250 then b weighs 400 minus 250 which is 150 can't tell you what the postage costs will be though.

auto98uk
05-03-2012, 15:32
To know there were millions of people who got this wrong I assume this has to be part of a news story somewhere, and yet I can't find it anywhere on the internet...

Are we actually doing your homework poppet2?

Jeffrey Shaw
05-03-2012, 15:35
Maybe the real question was supposed to ask the weight of B (not C)?

Jeffrey Shaw
05-03-2012, 15:37
To know there were millions of people who got this wrong I assume this has to be part of a news story somewhere, and yet I can't find it anywhere on the internet...
Yes, there was a BBC website a couple of days ago re this news item.
For the Daily Telegraph report, see http://www.telegraph.co.uk/education/maths-reform/9115665/Numeracy-Campaign-17m-adults-struggle-with-primary-school-maths.html
For the originator ('National Numeracy'), see http://www.nationalnumeracy.org.uk/news/9/index.htmlindex.html

auto98uk
05-03-2012, 15:40
Yes, a BBC news item.

You got a link?

edit: incidentally, just done exactly the same google search which previously brought this thread up as the top result, but the SF one has now vanished from the results.

Strix
05-03-2012, 15:45
Maybe the real question was supposed to ask the weight of B (not C)?
Some of us were taught maths which was supposed to have been given some context... leaving some of the class still unable to sort out which bits of real life needed to be taken into consideration and which bits ignored in order to actually use the learned skills in real life. This way kids are learning to sort out which pieces of information are relevant and which to ignore - a much better way of going about teaching if you ask me :)

auto98uk
05-03-2012, 15:45
Just found this page: http://www.thatquiz.org/tq/previewtest?L/T/F/X/02731308937894

The question is on there, but asking for the weight of parcel B, not C

Jeffrey Shaw
05-03-2012, 15:50
Just found this page: http://www.thatquiz.org/tq/previewtest?L/T/F/X/02731308937894

The question is on there, but asking for the weight of parcel B, not C
Aha! See my spookily prescient post #23.

poppet2
05-03-2012, 15:58
Maybe the real question was supposed to ask the weight of B (not C)?

Sorry everyone, a typing error, well spotted. Question asked for the weight of B.
Personally, I prefer who dunnit murder mysteries.

Jeffrey Shaw
05-03-2012, 16:00
Sorry everyone, a typing error, well spotted. Question asked for the weight of B.
Personally, I prefer who dunnit murder mysteries.
The answer is often Agatha Christie.

rubydazzler
05-03-2012, 16:05
Sorry everyone, a typing error, well spotted. Question asked for the weight of B.
Personally, I prefer who dunnit murder mysteries.d'oh, :rolleyes:

Whose mistake was it, that's caused us all the waste of time? Yours or the paper?

poppet2
05-03-2012, 16:11
The answer is often Agatha Christie.

King of them all has to be, 'Columbo'.'

SiSiSi
05-03-2012, 16:55
150...........

Alcoblog
05-03-2012, 17:54
Parcel 'B' obviously weighs 0.002755778273 of a pound or 0.00012302581595 of a ton (British) I think the parcel weight conundrum's been covered from every angle now ... pretty simple stuff.:)

corgigasman
05-03-2012, 18:07
If 'millions of adults' can not do the A,B,C parcel sum then WHO collected the statistics ? LOl. Prefer to think of kids doing times tables like I did myself rather than poorly worded, misleading questions. Can detect a soap box somewhere lol

gnvqsos
05-03-2012, 19:57
so C is half the weight of the total of 800 = 400
why do we need the weight of A? or am I missing something?

This si the sort of problem displayed at my lad's secondary school, so i don't know why they say its for primary school. Primary school for Oxbridge potentials perhaps? Might have been more sensionalist if they said it was for mums & baby's classes

The weight of A is added as a distractor,so as to confuse the weaker scholars.

gnvqsos
05-03-2012, 20:01
Is this maths or English comprehension?

It is both,since all questions have some written content.

poppet2
05-03-2012, 20:12
If 'millions of adults' can not do the A,B,C parcel sum then WHO collected the statistics ?

Many exam questions are multiple chioice and therefore marking is done by a computer.

gnvqsos
05-03-2012, 20:18
If 'millions of adults' can not do the A,B,C parcel sum then WHO collected the statistics ? LOl. Prefer to think of kids doing times tables like I did myself rather than poorly worded, misleading questions. Can detect a soap box somewhere lol

Anyone can recite tables,but problem-solving requires the ability to discriminate and think laterally.Many questions are ambiguous giving the respondent far greater scope.

WasThatWise
05-03-2012, 21:18
If a plus b weigh the same as c then both a plus b AND c weigh 400gms So if a weighs 250 then b weighs 400 minus 250 which is 150 can't tell you what the postage costs will be though.

I read the question wrong, the question turned out to be wrong and I got the answer right, who says two rights don't make a wrong?

Damn that should be two wrongs don't make a right so now I have three wrongs maybe I'll start a thread asking what three wrongs make unless someone thinks that would be wrong in which case I would then have four wrongs.

Emmie92
06-03-2012, 00:06
I read the question wrong, the question turned out to be wrong and I got the answer right, who says two rights don't make a wrong?


True :) I had to read the OP three times as it did not make sense. The question had to be wrong and it was. :hihi:

poppet2
06-03-2012, 12:33
Anyone can recite tables,but problem-solving requires the ability to discriminate and think laterally.Many questions are ambiguous giving the respondent far greater scope.

I agree, such problem solving mirrors everyday life situations which contributes to lateral thinking.

auto98uk
06-03-2012, 12:37
True :) I had to read the OP three times as it did not make sense. The question had to be wrong and it was. :hihi:

It makes perfect sense, it is just too easy and has superfluous information.

truman
06-03-2012, 12:57
True :) I had to read the OP three times as it did not make sense. The question had to be wrong and it was. :hihi:

Funny how some people managed to answer it though... :)

Phanerothyme
06-03-2012, 12:59
Funny how some people managed to answer it though... :)

Not only that but answer the question as written correctly.

Emmie92
06-03-2012, 13:03
Funny how some people managed to answer it though... :)

It was not impossible to answer just took a little more working out. :)

barleycorn
06-03-2012, 13:57
I agree, such problem solving mirrors everyday life situations which contributes to lateral thinking.

I am 37 years old and despite numerous visits to the post office I have never been faced with a situation in any way similar to the problem posed in the OP.

jb

poppet2
06-03-2012, 14:05
I am 37 years old and despite numerous visits to the post office I have never been faced with a situation in any way similar to the problem posed in the OP.

jb

Ah, but have you ever sat the post office examination entrance test?

barleycorn
06-03-2012, 14:21
Ah, but have you ever sat the post office examination entrance test?

Judging by some post offices I've been to it's the ones that fail who are given the jobs.

jb

Jeffrey Shaw
06-03-2012, 15:30
Ah, but have you ever sat the post office examination entrance test?
It must be written in post code.

SiSiSi
06-03-2012, 16:14
Question for the OP: so what is the answer?

gaz_no12
06-03-2012, 16:17
This type of thing always annoys me... how can so many adults not be able to do this. Lets just hope they pass this onto their kids

SiSiSi
06-03-2012, 16:19
This type of thing always annoys me... how can so many adults not be able to do this. Lets just hope they pass this onto their kids

So what's the answer?

spooky3
06-03-2012, 16:24
So what's the answer?

It's been shown here that the question was wrong!


Either way, whosoever is struggling with it have only got a primary understanding of basic maths (or worse!).

splodgeyAl
06-03-2012, 16:37
It's been shown here that the question was wrong!


Either way, whosoever is struggling with it have only got a primary understanding of basic maths (or worse!).The question is only wrong in so far as it, sensibly, should have asked for the weight of the other unknown parcel, which meant extraneous information was provided in the question.

However, a natural by-product of working out the weight of one of the unknown parcels is that you then know the weight of the other

spooky3
06-03-2012, 16:40
The question is only wrong in so far as it, sensibly, should have asked for the weight of the other unknown parcel, which meant extraneous information was provided in the question.

However, a natural by-product of working out the weight of one of the unknown parcels is that you then know the weight of the other

Can we have a question involving pulleys next please?

Or would this be the next logical step?
http://en.wikipedia.org/wiki/Simultaneous_equations

SiSiSi
06-03-2012, 16:40
Question isn't wrong, although my first attempt at it was! I gave the value of B.

If A+B+C=800 and A=250 then 250+150=400 ie. C=400.

spooky3
06-03-2012, 16:42
Question isn't wrong, although my first attempt at it was! I gave the value of B.

If A+B+C=800 and A=250 then 250+150=400 ie. C=400.

Re-read the thread, it was wrong!

Also you're missing a bit in your equation!

SiSiSi
06-03-2012, 16:43
Re-read the thread, it was wrong!

Also you're missing a bit in your equation!

Please explain what what was wrong.

spooky3
06-03-2012, 16:48
Please explain what what was wrong.

You left out this bit:

Parcels A and B together weigh the same as parcel C



As to the question being wrong:
Just found this page: http://www.thatquiz.org/tq/previewtest?L/T/F/X/02731308937894

The question is on there, but asking for the weight of parcel B, not C

Which makes sense.

SiSiSi
06-03-2012, 16:50
Question isn't wrong, although my first attempt at it was! I gave the value of B.

If A+B+C=800 and A=250 then 250+150=400 ie. C=400.

No I didn't.

splodgeyAl
06-03-2012, 16:51
You left out this bit:



As to the question being wrong:


Which makes sense.But as there are only 3 parcels, you know the weight of one and the total of the three. One would have to be spectacularly daft to calculate B but not know C.

The relevance of which one actually is the answer, only matters if the question is going to be marked, and that mark means something significant in your life, surely?

SiSiSi
06-03-2012, 16:52
But as there are only 3 parcels, you know the weight of one and the total of the three. One would have to be spectacularly daft to calculate B but not know C.

The relevance of which one actually is the answer, only matters if the question is going to be marked, and that mark means something significant in your life, surely?

So am I right or wrong?

spooky3
06-03-2012, 16:59
But as there are only 3 parcels, you know the weight of one and the total of the three. One would have to be spectacularly daft to calculate B but not know C.

The relevance of which one actually is the answer, only matters if the question is going to be marked, and that mark means something significant in your life, surely?

The superfluous information indicates to many that the question was obviously wrong in some way, this was then shown to be the case.

In the OP's example, you don't need to know the weight of A to work out the answer of C, but for B you need to know A.

SiSiSi
06-03-2012, 17:02
I'll ask again, am I right or wrong?

spooky3
06-03-2012, 17:05
I'll ask again, am I right or wrong?

LOL, specifically which bit?


*** have you seen post #60?

splodgeyAl
06-03-2012, 17:11
The superfluous information indicates to many that the question was obviously wrong in some wayIndeed, as I hinted at in post 6.

I'll ask again, am I right or wrong?
You have the right answer to the wrong question, apparently. But the wrong question was asked in this thread, so therefore you have the right answer to the right question (with respect to this thread)

Hope that helps ;)

poppet2
07-03-2012, 09:11
Question for the OP: so what is the answer?

See answer in post 5 and 57.
These posts include the weight of all parcels in the question.

barleycorn
07-03-2012, 09:50
Can we have a question involving pulleys next please?

Or would this be the next logical step?
http://en.wikipedia.org/wiki/Simultaneous_equations

I used simultaneous equations in my answer. And yes, I like to overcomplicate things.

jb

poppet2
07-03-2012, 10:14
I used simultaneous equations in my answer. And yes, I like to overcomplicate things.

jb

Please explain in binary code.

truman
07-03-2012, 10:16
Please explain in binary code.

there are 10 types of people in this world...those that understand binary and those that don't.. :)

barleycorn
07-03-2012, 10:24
Please explain in binary code.
01000001001000000010101100100000010000100010000000 11110100100000010000110010000001100001011011100110 01000010000001000001001000000011110100100000001100 10001101010011000000100000011100110110111100101110 00101110001011100000110100001010001010000011000100 10100100100000010000100010000000101101001000000100 00110010000000111101001000000010110100110010001101 01001100000000110100001010000011010000101001000001 00100000001010110010000001000010001000000010101100 10000001000011001000000011110100100000001110000011 00000011000000100000011000010110111001100100001000 00010000010010000000111101001000000011001000110101 00110000001000000111001101101111001011100010111000 10111000001101000010100010100000110010001010010010 00000100001000100000001010110010000001000011001000 00001111010010000000110101001101010011000000001101 00001010000011010000101000101000001100100010100100 10000000101101001000000010100000110001001010010000 11010000101001000010001000000010101100100000010000 11001000000011110100100000001101010011010100110000 00001101000010100100001000100000001011010010000001 00001100100000001111010010000000101101001100100011 01010011000000100000001011010000110100001010001100 10010000110010000000111101001000000011100000110000 00110000000011010000101001000011001000000011110100 10000000110100001100000011000000001101000010100100 00100010000000111101001000000011000100110101001100 00000011010000101000001101000010100110101001100010

jb

poppet2
07-03-2012, 10:44
Wow! I shall have to consult my Klingon dictonary.

truman
07-03-2012, 10:57
wow! I shall have to consult my klingon dictonary.

01011001011011110111010100100000011010100111010101 11001101110100001000000110111001100101011001010110 01000010000001110100011011110010000001100110011010 01011011100110010000100000011101000110100001100101 00100000011000110110111101110010011100100110010101 10001101110100001000000110001101101111011011100111 01100110010101110010011101000110010101110010001000 00011011110110111000100000011101000110100001100101 00100000011101110110010101100010001011100010111000 10111001101001011101000010011101110011001000000110 01010110000101110011011110010010000001110100011010 000110010101101110

MonkeyLover
08-03-2012, 08:05
Shouldn't the puzzle have been:

You have 3 parcels.

Parcels A and B together weigh the same as parcel C

What time will the postman sneak up to your house and put in a "sorry you weren't in" card through the letterbox without disturbing you because he couldn't be bothered carrying it from the depot?

What are the odds of all parcels being damaged or opened by Royal Mail?

:hihi::hihi::hihi: Brilliant!

Jeffrey Shaw
10-03-2012, 22:22
Wow! I shall have to consult my Klingon dictonary.
And your English dictionary?

cgksheff
11-03-2012, 13:14
01011001011011110111010100100000011010100111010101 11001101110100001000000110111001100101011001010110 01000010000001110100011011110010000001100110011010 01011011100110010000100000011101000110100001100101 00100000011000110110111101110010011100100110010101 10001101110100001000000110001101101111011011100111 01100110010101110010011101000110010101110010001000 00011011110110111000100000011101000110100001100101 00100000011101110110010101100010001011100010111000 10111001101001011101000010011101110011001000000110 01010110000101110011011110010010000001110100011010 000110010101101110


01101000011101000111010001110000001110100010111100 10111101110111011101110111011100101110011100100110 11110111010101100010011000010110100101111000011010 01011011100111010001100101011100100110000101100011 01110100011010010111011001100101001011100110001101 10111101101101001011110101000001101100011000010111 10010100011101110010011011110111010101101110011001 00001011110100001001101001011011100110000101110010 01111001010111110100001101101111011011100111011001 10010101110010011100110110100101101111011011100010 11110100001001101001011011100110000101110010011110 01010111110101010001101111010111110101010001100101 011110000111010000101110011000010111001101110000

denlin
11-03-2012, 14:08
King of them all has to be, 'Columbo'.'

No, he was runner up to Frost

truman
12-03-2012, 09:02
01101000011101000111010001110000001110100010111100 10111101110111011101110111011100101110011100100110 11110111010101100010011000010110100101111000011010 01011011100111010001100101011100100110000101100011 01110100011010010111011001100101001011100110001101 10111101101101001011110101000001101100011000010111 10010100011101110010011011110111010101101110011001 00001011110100001001101001011011100110000101110010 01111001010111110100001101101111011011100111011001 10010101110010011100110110100101101111011011100010 11110100001001101001011011100110000101110010011110 01010111110101010001101111010111110101010001100101 011110000111010000101110011000010111001101110000

01011001011001010111000000101100011101000110100001 10000101110100001001110111001100100000011101000110 10000110010100100000011011110110111001100101001000 00010010010010000001110101011100110110010100100000 01100001011100110010000001110111011001010110110001 101100

Jeffrey Shaw
12-03-2012, 12:02
Oh, stop it you two- or should that be 'stop it you 10'?

Tomm06
12-03-2012, 20:34
I read the question wrong, the question turned out to be wrong and I got the answer right, who says two rights don't make a wrong?

Damn that should be two wrongs don't make a right so now I have three wrongs maybe I'll start a thread asking what three wrongs make unless someone thinks that would be wrong in which case I would then have four wrongs.

Depends how you write it. Perhaps it could just mean Wrong^3 or if you write it wrong+wrong/wrong, two cancel out, leaving just wrong. I think, I'm afraid, 3 wrongs are just wrong lol.