Highgate Maths question

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Barnetmamma
Posts: 41
Joined: Sat Mar 22, 2014 12:10 am

Highgate Maths question

Post by Barnetmamma »

Can someone help with this maths question?

James has 15 sweets in his pocket. He has 7 red sweets, 6 blue sweets, and 2 pink sweets. Without looking, he removes some sweets from his pocket and places them on the table. What is the smallest number of sweets he should remove to guarantee that he has at least one sweet of each colour?

DD and I interpreted it differently. She thought it was related to having one of each colour in the ones he removed (she came up with 14), whereas I thought, it was about having one of each colour left in his pockets (I came up with 1).

Not sure which one of us is right... or perhaps even both wrong? :roll:
Guest55
Posts: 16254
Joined: Mon Feb 12, 2007 2:21 pm

Re: Highgate Maths question

Post by Guest55 »

I'd agree with you - if you take more than 1 then you might take all the pink sweets.
loobylou
Posts: 2032
Joined: Thu Nov 27, 2014 5:04 pm

Re: Highgate Maths question

Post by loobylou »

I read it as needing to guarantee one sweet of each colour on the table - so 14.
I can see that your (and G55) interpretation could be right as well but I would not have thought of that.
If that's the wording of the question then I don't think it's very clear.
Stokers
Posts: 358
Joined: Tue Aug 21, 2012 9:48 pm

Re: Highgate Maths question

Post by Stokers »

I think if it was sweets remaining in pocket, the word would be 'could' not 'should'. But, I agree - there should be an indication of whether it is sweets remaining in pocket or put on table
nyr
Posts: 1169
Joined: Thu Apr 04, 2013 11:39 am

Re: Highgate Maths question

Post by nyr »

I reckon it's 14 sweets, as the answer to "What is the smallest number of sweets he should remove to guarantee that he has at least one sweet of each colour?" would be:
14 if it referred to sweets on the table,
(probably) 0 if it referred to sweets in his pocket but this is unlikely to be the answer the examiner was expecting.

My feeling is that many indie maths papers have to be treated with some caution as I'm not sure that the questions are always carefully thought.
Guest55
Posts: 16254
Joined: Mon Feb 12, 2007 2:21 pm

Re: Highgate Maths question

Post by Guest55 »

If it doesn't mean the number taken from the sweets in his pocket then it is an appalling question.
Surferfish
Posts: 682
Joined: Fri Mar 10, 2017 5:06 pm

Re: Highgate Maths question

Post by Surferfish »

I think the answer they are looking for is 14, and that they probably are trying to say "What is the smallest number of sweets he should remove to guarantee that he has at least one sweet of each colour ON THE TABLE" rather than "What is the smallest number of sweets he should remove to guarantee that he has at least one sweet of each colour LEFT IN HIS POCKET". But agree that it is a very badly worded question.

As mentioned if they were talking about the sweets left in his pocket the answer would actually be zero, which is why I don't think this is the interpretation they meant. It also says he removes SOME sweets which implies more than one.
Guest55
Posts: 16254
Joined: Mon Feb 12, 2007 2:21 pm

Re: Highgate Maths question

Post by Guest55 »

He can remove one and be sure to have some of each type in his pocket.

James should not be eating sweets!
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