Go to navigation
It is currently Sat Mar 06, 2021 4:54 am

All times are UTC




Post new topic Reply to topic  [ 10 posts ] 
Author Message
 Post subject: Runners in a race
PostPosted: Fri Oct 20, 2017 6:59 pm 
Offline

Joined: Sat Jan 09, 2016 5:45 pm
Posts: 303
Hello all,

Just trying to compose a list of answers for DD. Would someone mind helping with the following?

Two runners are having a race. Gary starts running from the start line at 10m/s. Two seconds later Andy starts running from the start line at 12m/s.

How long after Gary starts running does Andy catch up with him?

How far are they both from the start line when Andy catches up with Gary?

Thank you!


Top
 Profile  
 
 Post subject: Re: Runners in a race
PostPosted: Fri Oct 20, 2017 7:11 pm 
Offline

Joined: Mon Feb 12, 2007 1:21 pm
Posts: 16253
MCLC wrote:
Two runners are having a race. Gary starts running from the start line at 10m/s. Two seconds later Andy starts running from the start line at 12m/s.

How long after Gary starts running does Andy catch up with him?

How far are they both from the start line when Andy catches up with Gary?

Gary has gone 20 m when Andy starts running - Andy is running 2 m/s faster so he takes 10 seconds to catch up - after 10 seconds he has gone 12 x 10 = 120 metres.

Or you could look at each second
GARY 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140,
ANDY 0, 0, 0, 12, 24, 36, 48, 60, 72, 84, 96, 108, 120,

If you line these up you can see the answer


Top
 Profile  
 
 Post subject: Re: Runners in a race
PostPosted: Fri Oct 20, 2017 7:33 pm 
Offline

Joined: Sat Jan 09, 2016 5:45 pm
Posts: 303
Thank you!

Sorry, how do I go about working out the second part of the question?


Top
 Profile  
 
 Post subject: Re: Runners in a race
PostPosted: Fri Oct 20, 2017 7:35 pm 
Offline

Joined: Mon Feb 12, 2007 1:21 pm
Posts: 16253
You should have both answers? 12 seconds and 120m.


Top
 Profile  
 
 Post subject: Re: Runners in a race
PostPosted: Fri Oct 20, 2017 7:37 pm 
Offline

Joined: Sat Jan 09, 2016 5:45 pm
Posts: 303
Ah I see, thanks. Is it better to draw out the options like you did in a question such as this?


Top
 Profile  
 
 Post subject: Re: Runners in a race
PostPosted: Fri Oct 20, 2017 7:54 pm 
Offline

Joined: Mon Feb 12, 2007 1:21 pm
Posts: 16253
I think I'd have tackled it the first way but a child can do it logicall the second way with no algebra or use of formulae.


Top
 Profile  
 
 Post subject: Re: Runners in a race
PostPosted: Mon Oct 23, 2017 12:13 pm 
Offline

Joined: Fri Mar 10, 2017 4:06 pm
Posts: 682
If Andy can run 120m in 10 seconds I'd suggest that he be tested for performance enhancing drugs! :shock:


Top
 Profile  
 
 Post subject: Re: Runners in a race
PostPosted: Mon Oct 23, 2017 12:21 pm 
Offline

Joined: Mon Feb 12, 2007 1:21 pm
Posts: 16253
Surferfish wrote:
If Andy can run 120m in 10 seconds I'd suggest that he be tested for performance enhancing drugs! :shock:

Just shows someone setting questions to work out easily without thinking if the answer is sensible - one of my pet hates. A bit like the one about a jug which contained 240 litres. :roll:


Top
 Profile  
 
 Post subject: Re: Runners in a race
PostPosted: Tue Oct 31, 2017 6:21 pm 
Offline

Joined: Mon Jan 24, 2011 4:33 pm
Posts: 1763
Guest55 wrote:
Surferfish wrote:
If Andy can run 120m in 10 seconds I'd suggest that he be tested for performance enhancing drugs! :shock:

Just shows someone setting questions to work out easily without thinking if the answer is sensible - one of my pet hates. A bit like the one about a jug which contained 240 litres. :roll:

I saw many odd things in my previous career. When Key Skills were introduced for apprentices, there was a call for maths problems to be contextualised. Nothing wrong with that of course, it's a very sensible thing to embed the maths apprentices need to demonstrate in problems they are likely to encounter in their discipline. Sadly, it quickly became apparent that there was a lazy way of doing things...

Original problem: A boat leaves shore at an angle of x degrees and travels x metres to a lighthouse, etc, etc.

"Contextualised" problem: A plumber is on a boat that leaves shore at an angle of x degrees..... :lol:


Top
 Profile  
 
 Post subject: Re: Runners in a race
PostPosted: Tue Oct 31, 2017 8:43 pm 
Offline

Joined: Mon Jun 18, 2007 2:32 pm
Posts: 7656
Location: East Kent
Diagrams and trial and improvement are perfect for KS2, it helps them work their way around a problem and think mathematically, which makes it so much easier for them to formalise this in secondary school.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 10 posts ] 

All times are UTC


Who is online

Users browsing this forum: No registered users and 9 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

Search for:
Jump to:  
Privacy Policy | Refund Policy | Disclaimer | Copyright © 2004 – 2021