It is currently Sun Jan 21, 2018 8:30 pm

 All times are UTC

 Page 1 of 1 [ 4 posts ]
 Print view Previous topic | Next topic
Author Message
 Post subject: Maths problemPosted: Thu Dec 27, 2007 3:53 pm
Can anyone help with the following question from the 2004 Habs Boys Maths paper:

A water tank is a cuboid with width 60cm, length 100cm and height 100cm.
a. Find the area of the base of the tank in square centimetres.
b. Use the fact that there are 1000 cubic centimetres in a litre to write down the volume of the tank in litres.
c. Initially the tank is half-full. Water is poured into the top of the tank at a constant rate of 30 litres per minute. How long will it take before the tank is three-quarters full?
d. At this point the tank springs a leak so that water pours out of the bottom at a constant rate of 15 litres per minute. If the water continues to be poured into the top at the same rate as before, how much longer will it be before the tank is full?

A worried mum.

Top

 Post subject: Posted: Thu Dec 27, 2007 7:25 pm
I think this is right...

a. area of base = l x w which is 60 x 100 = 6000cm2

b. volume = l x w x h which is 6000 x 100 = 600000cm2
then divide by 1000 to turn into litres = 600 litres.

c. 300 litres initially, rising to 450 litres is 150 litres to add.
At 30 litres per min this would take 150/30 = 5 mins.

d. Now the rate is halved to 30- 15 litres per min, i.e. 15 litres per min.
At 15 litres per min this would take 150/15 = 10 mins.

Top

 Post subject: Maths problemPosted: Thu Dec 27, 2007 8:24 pm
Hi Wallasey,

Many thanks for your clear and concise explanation.

Not so worried mum.

Top

 Post subject: Posted: Thu Dec 27, 2007 9:17 pm
Habs Maths 2004 is one of the papers we do not have in our Habs collection. So, I gave my son the question to solve, with the assurance that I did not have to work it all out as Wallasey had posted the answers!
My son solved the first 3 and wasn't too sure about the wording of the last one , but eventually understood it.
Please keep us posted with any others.

Top

 Display posts from previous: All posts1 day7 days2 weeks1 month3 months6 months1 year Sort by AuthorPost timeSubject AscendingDescending
 Page 1 of 1 [ 4 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