Math Is Fun Forum
You are not logged in.
- Topics: Active | Unanswered
Pages: 1
#1 2005-07-11 17:04:10
- Jai Ganesh
- Administrator
- Registered: 2005-06-28
- Posts: 48,424
Two cyclists
Two cyclists A and B go in circles,
A takes 1 hour to complete one circle,
and B completes 6 circles (the same circle as A) in an hour.
The question is, if the two start, in the same direction at
07.30 AM, when would they next cross each other?:)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
Offline
#2 2005-07-11 19:49:10
- mathsyperson
- Moderator
- Registered: 2005-06-22
- Posts: 4,900
Re: Two cyclists
Put in in the form of an equation. So,
[Ma loo ga wooga]
And all that means that they will next cross at [blah blah]
See, simple!:D
Why did the vector cross the road?
It wanted to be normal.
Offline
#3 2005-07-11 20:59:20
- MathsIsFun
- Administrator
- Registered: 2005-01-21
- Posts: 7,713
Re: Two cyclists
I think that by the time B has gone once around, A will have gone 1/6th around, then B just has to go that 1/6th further to catch A, but by then A will have moved further ... oh no, will he ever catch A?
"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman
Offline
#4 2005-07-11 23:29:30
- Jai Ganesh
- Administrator
- Registered: 2005-06-28
- Posts: 48,424
Re: Two cyclists
... oh no, will he ever catch A?
Reminds me of Zeno's Paradoxes!
B is faster than A and would get past him eventually!
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
Offline
#5 2005-07-11 23:32:36
- mathsyperson
- Moderator
- Registered: 2005-06-22
- Posts: 4,900
Re: Two cyclists
That's what I was thinking!
Why did the vector cross the road?
It wanted to be normal.
Offline
#6 2005-07-12 19:09:40
- Jai Ganesh
- Administrator
- Registered: 2005-06-28
- Posts: 48,424
Re: Two cyclists
Speed = Distance travelled / Time taken
Let the distance travelled in 1 circle be C Units.
Speed of A = C Units/hour and Speed of B=6C Units/hour.
Last edited by Jai Ganesh (2005-07-12 22:08:10)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
Offline
#7 2005-07-12 20:52:22
- mathsyperson
- Moderator
- Registered: 2005-06-22
- Posts: 4,900
Re: Two cyclists
I got that, but edited it after about 2 minutes.
Why did the vector cross the road?
It wanted to be normal.
Offline
#8 2005-07-12 21:36:53
- Jai Ganesh
- Administrator
- Registered: 2005-06-28
- Posts: 48,424
Re: Two cyclists
Maybe, I should have waited for some more days
before giving the solution.
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
Offline
#9 2005-07-12 21:38:14
- MathsIsFun
- Administrator
- Registered: 2005-01-21
- Posts: 7,713
Re: Two cyclists
Or even longer ... give all visitors a chance.
(Wow, B DOES get past A ! 
)
"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman
Offline
#10 2005-07-12 21:53:11
- mathsyperson
- Moderator
- Registered: 2005-06-22
- Posts: 4,900
Re: Two cyclists
Is it possible to use BBCode to make 'invisible writing' that you need to copy and paste to read?
Just a thought.
Why did the vector cross the road?
It wanted to be normal.
Offline
#11 2005-07-13 00:04:44
- MathsIsFun
- Administrator
- Registered: 2005-01-21
- Posts: 7,713
Re: Two cyclists
The text could be the same colour as background ... I could delve into PunBB code to see if that is possible.
"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman
Offline
#12 2005-07-13 00:07:19
- mathsyperson
- Moderator
- Registered: 2005-06-22
- Posts: 4,900
Re: Two cyclists
Would it work even though it's possible to have different 'visual styles' and hence different coloured backgrounds?
Why did the vector cross the road?
It wanted to be normal.
Offline
#13 2005-07-13 00:26:03
- MathsIsFun
- Administrator
- Registered: 2005-01-21
- Posts: 7,713
Re: Two cyclists
It may or may not be hard, depending on whether I can apply the "current" background style to the text. I won't know till I have a look.
And I don't know how to extend BBCode, but there should be a way.
Hmmm ... what would we call the BBCode? [ ??? ]
"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman
Offline
#14 2005-07-13 03:41:15
- Roraborealis
- Member
- Registered: 2005-03-17
- Posts: 1,594
Re: Two cyclists
Call it? YAY!!!!!! Another name-making-up thingy! (the last was for the new board)
School is practice for the future. Practice makes perfect. But - nobody's perfect, so why practice?
Offline
#15 2005-07-13 08:44:29
- Zach
- Member
- Registered: 2005-03-23
- Posts: 2,075
Re: Two cyclists
You can do it in PHPBB, so I expect it's possible on PunBB. Perhaps editing the CSS, if you can?
Boy let me tell you what:
I bet you didn't know it, but I'm a fiddle player too.
And if you'd care to take a dare, I'll make a bet with you.
Offline
#16 2005-07-13 09:57:00
- MathsIsFun
- Administrator
- Registered: 2005-01-21
- Posts: 7,713
Re: Two cyclists
Probably a combination of code and CSS. I will have a look in a coupla days.
Name Idea: whisper
"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman
Offline
#17 2005-07-14 16:44:39
- tt
- Member
- Registered: 2005-07-03
- Posts: 32
Re: Two cyclists
They will cross each other at 7:42AM.
Offline
#18 2005-07-14 19:03:04
- justlookingforthemoment
- Moderator
- Registered: 2005-05-26
- Posts: 2,161
Re: Two cyclists
shadow
or
silhouette
Offline
#19 2005-07-14 19:34:20
- MathsIsFun
- Administrator
- Registered: 2005-01-21
- Posts: 7,713
Re: Two cyclists
I like those names.
Apparently the search engines HATE invisible text because spam sites use it to misdirect people to their site. You know, mention important words several times at the bottom of the page even if it isn't part of the site. So advise I have seen said you can be banned by the search engines for using it.
So, I have thought "what about just hard-to-read text?" You know it is there, so no deceit, but you have to run your mouse across it to read it or something.
So maybe White Text or some clever "CSS" stuff.
"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman
Offline
#20 2005-07-14 19:37:32
- mathsyperson
- Moderator
- Registered: 2005-06-22
- Posts: 4,900
Re: Two cyclists
It's that kind of thing that makes Tony Blair's site a top hit in a google search for 'Liar' and George W Bush's site a top hit in a google search for 'miserable failure'. It only works with google though, because they search in a different way to all other search engines.
Also, some of the 'visual styles' display text as white anyway, so that wouldn't always work.
Why did the vector cross the road?
It wanted to be normal.
Offline
Pages: 1