View unanswered posts  View active topics

Page 1 of 1

[ 4 posts ] 

Author 
Message 
silverysea

Posted: Wed Aug 07, 2013 5:04 pm 

Joined: Fri Mar 04, 2011 2:32 pm Posts: 965

For superselective, do they need to be able to calculate the area of a circle? Tutor did this today but I've not seen it in any test papers tried so far.


Top 


leanmeamum

Posted: Fri Aug 09, 2013 8:47 am 

Joined: Sat Dec 03, 2011 3:14 pm Posts: 654

they give the formula for the area of a circle or the area, if there is a question involving it.
Maybe the tutor covered the topic just to show how it works so it is easy for the child to see understand circles


Top 


silverysea

Posted: Fri Aug 09, 2013 8:56 am 

Joined: Fri Mar 04, 2011 2:32 pm Posts: 965

Ok that does help! It's all about familiarity I guess!


Top 


parent2013

Posted: Mon Aug 12, 2013 10:48 am 

Joined: Mon Aug 12, 2013 9:13 am Posts: 452

The answer unfortunately is "Yes" for superselectives. I have seen numerous examples in private school papers from previous years where this concept has been tested. It is not rocket science and there are only 2 formulas to remember.
Circumference : 2 X Pi X Radius (where Pi is 3.14 or 3 for approximation) OR Pi X Diameter (as Diameter is twice the radius)
Area: Pi X (square of radius)
One example I remember from top of the head is: 1. Ben has a bicycle with a wheel of radius 1m, how much distance it covers in 10 turns
Using Pi = 3, the distance in one turn is the circumference i.e. 2 X 3 X 1 = 6m. Therefore in 10 turns, it will cover a distance of 10 X 6m i.e. 60m.
2. His grandfather "John" has a bicycle with a bigger wheel of radius 1.5m, how much additional distance it covers in 10 turns? Using Pi = 3, the distance in one turn is the circumference i.e. 2 X 3 X 1.5 = 9m. Therefore in 10 turns, it will cover a distance of 10 X 6m i.e. 90m. The answer is "additional" distance i.e. 9060 = 30m.


Top 



Page 1 of 1

[ 4 posts ] 

Who is online 
Users browsing this forum: Karla Tyler and 3 guests 

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