Perimetre of a room - Bond paper

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sherry_d
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Location: Maidstone

Perimetre of a room - Bond paper

Post by sherry_d »

I am struggling with the answer for this question. Its some 12 shape room on question 28 in Bond Paper 2.

I always thought that perimetre in 2(length) + 2 (width) and that the same fomular applies for wonky shapes too. It seems I am wrong in this case as they have manually added all the sides. Can you please advice me on how to find perimeter of odd shapes please.
Impossible is Nothing.
moved
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Re: Perimetre of a room - Bond paper

Post by moved »

If the shape has had a corner cut off then it will still be 2 (width + length) as the lines could be moved to the correct places, but if it has a chunk cut from a side then you will have at least one extra line so this must be counted.

________
| __|
| |__
| |
|_______|

All the spaces have disappeared when it posts. Perhaps someone else can provide a picture.
sherry_d
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Location: Maidstone

Re: Perimetre of a room - Bond paper

Post by sherry_d »

Yep the rectangle has 2 chunks cut of on both sides.

I am getting the answer as 32 and yet the correct answer is 37 (which is what you get when all 12 sides are added together).

I have always gone with 2(length) + 2 (widths) even when the shapes has chunks taken out and today this has thrown my answer out.

(If anyone has Bond test papers can you help me out please its Question 28 Test 2)
Impossible is Nothing.
Amber
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Re: Perimetre of a room - Bond paper

Post by Amber »

Interesting that some words instantly get zapped by the website, but sherry_d's wonderful description of a shape has made it through. Especially perfect with the reference to 'manually' in the next line. I must have a homing device - never looked at the Maths section before!
stevew61
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Location: caversham

Re: Perimetre of a room - Bond paper

Post by stevew61 »

Fixed. :)
stevew61
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Location: caversham

Re: Perimetre of a room - Bond paper

Post by stevew61 »

DS2 has a problem with perimeters trying to work out all the little bits and wasting lots of time.

This is visual but often you can move lines and the shape reverts to a rectangle, which is what I think Moved was trying to say/draw?

Or a rectangle plus a little bit extra. :)

In this case a picture is better than many words.
Amber
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Joined: Thu Sep 24, 2009 11:59 am

Re: Perimetre of a room - Bond paper

Post by Amber »

stevew61 wrote:Fixed. :)
You've spoiled my fun, and made everyone wonder what I was on about!
mad?
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Re: Perimetre of a room - Bond paper

Post by mad? »

Amber wrote:
stevew61 wrote:Fixed. :)
You've spoiled my fun, and made everyone wonder what I was on about!
no, still fun! I have re read the post and put 2 and 2 together! :lol:
mad?
stevew61
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Joined: Fri Nov 17, 2006 9:54 pm
Location: caversham

Re: Perimetre of a room - Bond paper

Post by stevew61 »

Sorry Amber but you do win a prize for being an eagle eye. :)

If anyone is interested in the typo then PMs please.

Oh and no testing the system. :)
Amber
Posts: 8058
Joined: Thu Sep 24, 2009 11:59 am

Re: Perimetre of a room - Bond paper

Post by Amber »

I showed this thread to OH and he said ' a bit puerile, isn't it?' and I said 'a little light relief never hurt anyone.' I won't tell you his reply.

I would love to know how many pm you for the typo stevew!
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