Help with VR
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Help with VR
Can anyone tell me how to approach the following style question:
Use three of the numbers on the left once only to make up the number you are given.
7,9,11,13,16 : 31= ( + + )
My daughter didn't know where to start with these - are there any techniques I can tell her to use?
Use three of the numbers on the left once only to make up the number you are given.
7,9,11,13,16 : 31= ( + + )
My daughter didn't know where to start with these - are there any techniques I can tell her to use?
Re: Help with VR
I would try trial and error to begin with.
16 + 13 = 29 ..can;t be those two as there is no 2 etc. afetr a while she will get a feel for which numbers are likely. Lots of practice.
I haven;t seen examples like this before.
Where are you based?
Is this a multiple choice question or standard?
16 + 13 = 29 ..can;t be those two as there is no 2 etc. afetr a while she will get a feel for which numbers are likely. Lots of practice.
I haven;t seen examples like this before.
Where are you based?
Is this a multiple choice question or standard?
Re: Help with VR
Thanks for replying so quickly!
We live in Lincolnshire. It is standard format and so can be very time consuming! I haven't seen many of these type of questions either, maybe they are just specific to Lincs. Maths is not my daughter's strong point which is why I'm a bit worried.
We live in Lincolnshire. It is standard format and so can be very time consuming! I haven't seen many of these type of questions either, maybe they are just specific to Lincs. Maths is not my daughter's strong point which is why I'm a bit worried.
Re: Help with VR
Have a look at the Susan J. Daughtrey method & technique books.
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http://www.elevenplusexams.co.uk/books/list.php?g=f&p=7" onclick="window.open(this.href);return false;Books 1, 2, 3 and 4 cover the TECHNIQUE and PRACTICE of each of the 35 Types of question. Book 1 covers the first 13 Types, book 2 covers 10 Types and the remaining Types are dealt with in books 3 and 4 deals specifically with maths and code questions.
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Re: Help with VR
hi,staffakh wrote:Can anyone tell me how to approach the following style question:
Use three of the numbers on the left once only to make up the number you are given.
7,9,11,13,16 : 31= ( + + )
I have not come across this type of question before, but I would suggest that you take one number away from the 31 and then see if the remainder can be made by two of the other numbers.
eg, 31-7 = 24, can 24 be made by two others?
31- 9= 22, can 22 be made by two others?
31- 11= 20, can 20 be made by two others? 7+13 = 20
so the answer is 7+13+11 (I think!)
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Re: Help with VR
The question "which numbers from this list add up to this number?" turns out to be, in general, extremely hard and very interesting. It's nice to have a problem which is simple enough, in a small example, to make an 11+ question, but leads on to some fairly challenging (undergraduate, or possibly just on the outer limits of A Level) theory by just adding some more numbers to the question.
Suppose I gave you a hundred numbers and asked you to choose the ones that added up to some other number. How long did it take you? Now, suppose I give you a thousand numbers and give you ten times longer than it took with a hundred numbers. Can you do it?
Manage that and you're well on your way to a million dollars. No, really, a million dollars.
http://www.claymath.org/millennium/P_vs_NP/" onclick="window.open(this.href);return false;
http://en.wikipedia.org/wiki/Subset_sum_problem" onclick="window.open(this.href);return false;
Suppose I gave you a hundred numbers and asked you to choose the ones that added up to some other number. How long did it take you? Now, suppose I give you a thousand numbers and give you ten times longer than it took with a hundred numbers. Can you do it?
Manage that and you're well on your way to a million dollars. No, really, a million dollars.
http://www.claymath.org/millennium/P_vs_NP/" onclick="window.open(this.href);return false;
http://en.wikipedia.org/wiki/Subset_sum_problem" onclick="window.open(this.href);return false;