It is currently Sat Dec 03, 2016 5:43 pm

 All times are UTC

 Page 1 of 3 [ 23 posts ] Go to page 1, 2, 3  Next
 Print view Previous topic | Next topic
Author Message
 Post subject: maths -number sequencePosted: Sun May 09, 2010 4:19 pm

Joined: Wed Dec 09, 2009 12:59 pm
Posts: 11
Pls help, my DD can't work these out. Neither can I!!

1. What is the answer to this nimber sequence
1 2 4 8 10 20 ____ ____ .

2. Paul is given a box of 45 chocolates. His brother eats 20%and his mum eats 2/5. How many chocolates are left for Paul?

Top

 Post subject: Posted: Sun May 09, 2010 4:31 pm

Joined: Tue May 05, 2009 9:26 pm
Posts: 439

20% = 1/5. So 3/5 are eaten ie 27 ( 45 divided by 5 = 9. Then x 3). Therefore 45 - 27 = 18.

Top

 Post subject: Posted: Sun May 09, 2010 4:35 pm

Joined: Tue May 05, 2009 9:26 pm
Posts: 439
Question 1:

The next two nos are 22 and 44.

THere are two difference alternating sequences here:

1,4 10 22

and

2,8,20 and 44

The difference between the nos in the first sequence doubles, so the differences are 3,6,12

The difference between the nos in the second sequence doubles too, so the differences are 6, 12, 24

Top

 Post subject: Posted: Sun May 09, 2010 4:36 pm

Joined: Mon Dec 10, 2007 9:55 pm
Posts: 18
Question 1: The pattern is x2, +2 so the next two numbers are 22, 44

Top

 Post subject: Posted: Sun May 09, 2010 4:36 pm

Joined: Wed Apr 28, 2010 11:19 am
Posts: 294
DD thinks the first one is a leapfrog sequence, ie 2 sequences in one

1..... 4..... 10..... ?
+3 +6 therefore next in sequence is +12 so 1st ? is 22

2..... 8 ..... 20 ..... ?
+6 +12 therefore next in sequence is +24 so 2nd ? is 44

The second problem is...
Paul is given a box of 45 chocolates. His brother eats 20% ie 1/5
and his mum eats 2/5. How many chocolates are left for Paul? so 1/5 + 2/5 = 3/5 have been eaten, this leaves 2/5 of 45 = 18 chocs left for Paul.

_________________
www.TickerFactory.com/weight-loss]

Top

 Post subject: Posted: Sun May 09, 2010 4:38 pm

Joined: Tue May 05, 2009 9:26 pm
Posts: 439
Gosh how interesting that we have approached question 1 completely differently and got the same answers!

Top

 Post subject: Posted: Sun May 09, 2010 6:03 pm

Joined: Wed Dec 09, 2009 12:59 pm
Posts: 11
Hi guys,

Thanks for answering so promptly. DD and I understand it now.

Top

 Post subject: Posted: Mon May 10, 2010 9:29 am

Joined: Fri Sep 11, 2009 10:10 am
Posts: 52
I totally understand the approach for Q1 (the number sequence) with answers 22 and 44.It makes complete sense.

But when given this question, one of the answers that came up in the discussion at home was :

1, 2,4,8, 10, 20, 40, 80, 100, 200, 400, 800, 1000, 2000, 4000, 8000 and so on.

In this case, the next two numbers would be 40, 80.
This is a sequence of repetitions. Shouldn't this kind of approach be ever applied for a 11+ Maths ?

Top

 Post subject: Posted: Mon May 10, 2010 9:40 am

Joined: Tue May 05, 2009 9:26 pm
Posts: 439
I think that there is not sufficient evidence in the string of nos given in the question for that type of approach.

Top

 Post subject: Posted: Mon May 10, 2010 10:29 am

Joined: Tue Sep 01, 2009 3:38 pm
Posts: 2083
Location: Maidstone
Thats what I thought at first too Abr but then there is 8 to 10 which throws out that sequence.

_________________
Impossible is Nothing.

Top

 Display posts from previous: All posts1 day7 days2 weeks1 month3 months6 months1 year Sort by AuthorPost timeSubject AscendingDescending
 Page 1 of 3 [ 23 posts ] Go to page 1, 2, 3  Next

 All times are UTC

#### Who is online

Users browsing this forum: No registered users and 2 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