It is currently Sun Dec 04, 2016 3:56 am

 All times are UTC

 Page 1 of 10 [ 91 posts ] Go to page 1, 2, 3, 4, 5 ... 10  Next
 Print view Previous topic | Next topic
Author Message
 Posted: Sun Jan 04, 2015 8:04 pm

Joined: Sat Jan 03, 2015 4:26 pm
Posts: 189

My daughters just done this and am struggling with the answers trying to re live my youth or rather I need to confirm the correct answers for all especially Questions 21-26, 30 .

Here's the link below please. think its easier rather than trying to type each question here.
http://habsboys.org.uk/info/examination ... plus13.pdf

Your help will be much appreciated.

Many thanks to you Maths Gurus

Last edited by Mittleme on Sun Jan 04, 2015 9:12 pm, edited 1 time in total.

Top

 Posted: Sun Jan 04, 2015 8:55 pm

Joined: Fri Oct 12, 2007 12:42 pm
Posts: 3810
Could you post a link to the paper or type in the questions. Not everyone knows all papers by heart.

Top

 Posted: Sun Jan 04, 2015 10:01 pm

Joined: Thu Apr 04, 2013 10:39 am
Posts: 651
Q21)
8 people take 3 hours
10 people can paint a fence twice as long in under 5 hours

Q22)
3/4, 7/8, 15/16, 1023/1024, ..., 1

Q23)
11*17 = 187 runs
(187-2*39.5)/9 = 12 runs per remaining batsmen

Q24)
40 strips
40*30m = 1200m
40*75s = 3000s = 50 minutes (includes time for 39 turns and 1 start)

Q25)
(3,2)
(5,3)
(9,9)
(21,22)

Q26)
Regular pentagon, a = 360/5 = 72, b = (180-72)/2 = 54
Regular hexagon, a = 360/6 = 60, b = (180-60)/2 = 60

Q30)
Position and possible runners
1st is 5 or 7 or 11 or 13
2nd is 6 or 8 or 12
3rd is 8
4th is 5 or 10
5th is 11
6th is 12 or 14
7th is 11 or 14
8th is 6, 8, 10, 14
9th is 8 or 9
10th is 11 or 12 or 13 or 14

Position and actual runners
1st is 7
2th is 6
3th is 8
4th is 5
5th is 11
6th is 12
7th is 14
8th is 10
9th is 9
10th is 13

nyr

Last edited by nyr on Mon Jan 05, 2015 10:13 am, edited 1 time in total.

Top

 Posted: Sun Jan 04, 2015 10:24 pm

Joined: Sat Jan 03, 2015 4:26 pm
Posts: 189
thank you so much for the quick response nyr

on nos 30. my daughter had as

Positions in Race Number of Runners
1st - 7
2nd - 6
3rd - 8
4th - 5
5th - 11
6th -12
7th - 14
8th - 10
9th - 9
10th - 13

i thought we can't have an answer twice like you had 5 twice. Please correct me if am wrong though.

Thank you

Top

 Posted: Sun Jan 04, 2015 10:33 pm

Joined: Thu Apr 04, 2013 10:39 am
Posts: 651
You're right, I missed out 7 from my list of primes and then failed to spot that runner 5 finished in 2 positions in my answer. So, you're right, runner 7 finished in 1st position.

Top

 Posted: Mon Jan 05, 2015 9:37 am

Joined: Thu Jun 14, 2012 9:28 am
Posts: 121
nyr,
Thank you for posting the answers. I am an interested (in my child's education) parent. My nephew, who is also revising for his 11+ had a different answer to the last part of question 25, it being (21,22) which I though was correct until I saw your answer. Perhaps you could elaborate on how you arrived at your answer. Many thanks and a Happy New Year!
Tagore

Top

 Posted: Mon Jan 05, 2015 10:15 am

Joined: Thu Apr 04, 2013 10:39 am
Posts: 651
Tagore, you're right. It should be (21,22).

Top

 Posted: Mon Jan 05, 2015 12:45 pm

Joined: Sat Jan 03, 2015 4:26 pm
Posts: 189
Hi nyr

1. Please explain Nos 26 ( the question with five sided and 6 sided polygon)
where you have divided by 2.

i know we have been given a clue that all sides are equal .

what clue tells us the angles are equal as well( since you have divided by 2)

2. also please kindly help answer the last part of the same Question that asks for the Name of the triangle ABC?

Many Thanks

Top

 Posted: Mon Jan 05, 2015 2:20 pm

Joined: Thu Apr 04, 2013 10:39 am
Posts: 651
Mittleme, I assume you accept that angle a can be calculated as in my earlier answer, so we can move on to angle b and let us consider either of these polygons.

Since each corner of the pentagon (or hexagon) is equidistant to its centre, we know that AB and AC are the same length. So, the angle b and the third angle, say c, are the same - from the properties of an isosceles triangle.

The question tells us that the angles in a triangle add up to 180, so b+c=2b=180-a. Therefore b = (180-a)/2.

In the case of the regular pentagon, triangle ABC is called an isosceles triangle, where two angles and hence the length of two edges are the same.

In the case of the regular hexagon, triangle ABC is called an equilateral triangle, where all angles and hence the length of all edges are the same.

Does that help?

Top

 Posted: Mon Jan 05, 2015 5:35 pm

Joined: Sat Jan 03, 2015 4:26 pm
Posts: 189
Thank you Once again nyr.

ok i understand all your explanation up till the last paragraph

In the case of the regular hexagon, triangle ABC is called an equilateral triangle, where all angles and hence the length of all edges are the same.

i dont mean to be thick here but i like to understand what am being taught . i have completely forgotten some of my maths and i have googled but can't find anything

My question is
so what tells me in the diagram that ABC is equilateral(of course this means where all angles and hence the length of all edges are the same.)

. is this one of the property of a regular hexagon? or does the thickened dark lines mean equal lengths?

same for the pentagon?
Thanks in anticipation

Top

 Display posts from previous: All posts1 day7 days2 weeks1 month3 months6 months1 year Sort by AuthorPost timeSubject AscendingDescending
 Page 1 of 10 [ 91 posts ] Go to page 1, 2, 3, 4, 5 ... 10  Next

 All times are UTC

Who is online

Users browsing this forum: Yahoo [Bot] and 1 guest

 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