It is currently Tue Jan 16, 2018 9:54 am

 All times are UTC

 Page 1 of 1 [ 7 posts ]
 Print view Previous topic | Next topic
Author Message
 Post subject: Area question. Could you help, please.Posted: Sun Sep 07, 2008 1:20 pm

Joined: Thu Aug 16, 2007 8:40 pm
Posts: 5
Dear all,
Please, could you help with this question.

(The picture given is like a photo frame- one rectangle inside another. The outer rectangle's sides are 1.6 m and 2.4 m. The inner rectangle is labeled Plain tiles, and the frame is labelled Border tiles).

Masih is going to tile a floor which is 2.4 m by 1.6 m.
All the tiles are 20 cm square.
He is going to put one layer of border tiles around the edge.
How many tiles does he need to fill in the middle?

The answer is 60. But how do you work it out? Thanks.

Top

 Post subject: Posted: Sun Sep 07, 2008 3:13 pm

Joined: Tue Dec 13, 2005 12:49 pm
Posts: 1647
Location: berkshire
If you look at the diagram you can see that the inner rectangle will be 2 tiles shorter and 2 tiles narrower than the outer triangle i.e. 2 x 20 cm giving 40cm narrower and shorter.

Therefore 2.4 less 40cm = 2m and 1.6 less 40cm = 1.2

The inner triangle would be 2m x 1.2m (or 10 tiles by 6 tiles) giving 60 tiles.

Top

 Post subject: Posted: Sun Sep 07, 2008 4:00 pm

Joined: Thu Aug 16, 2007 8:40 pm
Posts: 5
Yes, the inner rectangle is 2 tiles shorter and 2 tiles narrower than the outer rectangle.
But we can not say that it is 40 cm narrower and shorter because we do not know how much the side of each tile is.
What we are given is that an area of each tile is 20 cm square, so each side can not be 20 cm in length.
I have been trying to work this out since yeasterday, and it did not make sense with the information given.
I have concluded that there must be a mistake, and the info given should state that each tile's side is 20 cm, not each tile's area is 20 cm square. Then you can work out the answer in this way.

Top

 Post subject: Posted: Sun Sep 07, 2008 4:08 pm

Joined: Thu Aug 16, 2007 8:40 pm
Posts: 5
You know what...
It's as simple as that!
...tiles 20 cm square mean that all tiles are square shape with 20 cm each side. But when I looked at the word 'square' I thought of an area, not a shape.
More you look, less you see.

Top

 Post subject: Posted: Sun Sep 07, 2008 7:05 pm

Joined: Wed Jan 02, 2008 12:18 pm
Posts: 490
Location: kent
Yes I would have learned this phraseology at school - something 20 cm square but how many people would be taught it these days. It's another example of the old-fashioned stuff that pops up in the 11+ that has nothing to do with IQ.

Top

 Post subject: Posted: Sun Sep 07, 2008 7:15 pm

Joined: Mon Feb 12, 2007 1:21 pm
Posts: 13989
It's a very common way of talking about the dimensions of a square -

For an area you would say 20 cm squared or 20 square cm.

Top

 Post subject: Posted: Sun Sep 07, 2008 9:04 pm

Joined: Thu Aug 16, 2007 8:40 pm
Posts: 5
My DD thought of tiles with an area of 20, just like me. I think this type of question could have been better phrased for children.
What could be learnt from this scenario:
If the numbers don't add up or the situation doesn't make sense - try an alternative thinking and look at the question with fresh ideas reading every word again.
I always tell my children that a solution hides in a question itself.

Top

 Display posts from previous: All posts1 day7 days2 weeks1 month3 months6 months1 year Sort by AuthorPost timeSubject AscendingDescending
 Page 1 of 1 [ 7 posts ]

 All times are UTC

#### Who is online

Users browsing this forum: No registered users and 3 guests

 You cannot post new topics in this forumYou cannot reply to topics in this forumYou cannot edit your posts in this forumYou cannot delete your posts in this forumYou cannot post attachments in this forum

Search for:
 Jump to:  Select a forum ------------------ FORUM RULES    Forum Rules and FAQs 11 PLUS SUBJECTS    VERBAL REASONING    MATHS    ENGLISH    NON-VERBAL REASONING    CEM 11 Plus GENERAL    GENERAL 11 PLUS TOPICS    11 PLUS APPEALS    11 PLUS TUTORS    INDEPENDENT SCHOOLS    11 PLUS CDs/SOFTWARE    11 PLUS TIPS    PRIMARY    SEN and the 11 PLUS    EVERYTHING ELSE .... 11 PLUS REGIONS    Berkshire    Bexley and Bromley    Birmingham, Walsall, Wolverhampton and Wrekin    Buckinghamshire    Devon    Dorset    Essex    Essex - Redbridge    Gloucestershire    Hertfordshire (South West)    Hertfordshire (Other and North London)    Kent    Lancashire & Cumbria    Lincolnshire    Medway    Northern Ireland    Surrey (Sutton, Kingston and Wandsworth)    Trafford    Warwickshire    Wiltshire    Wirral    Yorkshire BEYOND 11 PLUS    Beyond 11 Plus - General    GCSEs    6th Form    University