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PersianBulldog
02-12-2003, 02:57 PM
I have a tricky question for y&#39;all.. Let&#39;s see who&#39;ll solve it first&#33;

Imagine you&#39;re on a train. This train goes from A to B. It takes 5h to get from A to B. One train goes from B to A every hour.
If you are going to go to B, how many trains will you see on the way?

Show me how you&#39;ve solved it too..

//P.Bull

R) Edited the thing Cyn said..

Cyn v4.1
02-12-2003, 03:27 PM
none. the trains leaving B were never said to be going to A.
if you wanted us to assume that B was going to A...
go F00k yourself. ;)

artmaster88
02-12-2003, 03:30 PM
i&#39;d say ten, but that was just a thought, cuz you&#39;ll meet one every hour, and since both trains move they will meet every half an hour. i could be wrong though.. but only if the trains leaving B go to A

dwightfry
02-12-2003, 04:16 PM
I&#39;d say 6. As you are leaving point A, you will see the first one coming in, and when you get to point B, you will see the 6th one leaving.

DID I GET IT, DID IT GET IT&#33;?&#33;?&#33;?&#33;?&#33;? :lol: :D :lol: :D :P

VB
02-12-2003, 04:23 PM
10

Dan
02-12-2003, 04:33 PM
plaul tad a nice pic i C U have therrrrrr r r r r rr r r r sorry e jfoiadl ok

dwightfry
02-12-2003, 04:44 PM
By this logic, I don&#39;t think 10 is correct because that is saying that the ratio is 2:1
(train 1 takes 2 hours, while train 2 takes 1 hour)
So train 2 is going 2 times faster

This would be 5:1
(train 1 takes 5 hours, while train 2 takes 1 hour)
Train 2 is going 5 times faster

so it may actually be 25 times.

If you count the trains that is just leaving while you are ariving, that would make it 26

But that can&#39;t be right either, because that would be saying that for every 1 hour you would see 5 trains....and that&#39;s not right.

Cyn v4.1
02-12-2003, 04:48 PM
well, just because a train leaves B every hour does not mean it has to arrive at point A in an hour.

dwightfry
02-12-2003, 04:49 PM
I&#39;m sticking with my answer of 6.

For every hour train one goes, 1.2 trains would go into the oppisite direction. so if train 1 goes for 5 hours, that would be 6 full trains.

I got 1.2 because 5 devided by 1 is .2

Knuckles187
02-12-2003, 05:34 PM
Originally posted by Cyn v4.1@12 February 2003 - 16:48
well, just because a train leaves B every hour does not mean it has to arrive at point A in an hour.
This post has been edited by PersianBulldog on 12 February 2003 - 15:33

This post has been edited by PersianBulldog on 12 February 2003 - 15:33
This post has been edited by PersianBulldog on 12 February 2003 - 15:33

perhaps you now are the fool....

but either way i would say.. 8 because it is a random number that nobody else has chosen so far/...

smellycat
02-12-2003, 05:46 PM
Assuming the trains from A and B start at the same minutes past the hour.

When you start on your journey, the train from B would have arrived.
You haven&#39;t passed it so it doesn&#39;t count.
An hour later and you would have been past by 1 train
Another hour later and you would have been past by 1 train
Another hour later and you would have been past by 1 train
Another hour later and you would have been past by 1 train
Another hour later and you arrive at the station. The train is just about to pull off.
You haven&#39;t passed it so it doesn&#39;t count.

Total Number of trains passing you = 4

Can you guys be in charge of calculating my wages? :D

Cyn v4.1
02-12-2003, 05:53 PM
i wonder what that guy said that got edited
maybe it was about the fact that if the B train didnt arrive to A in an hour they would crash into each other.
i see my error.

artmaster88
02-12-2003, 05:58 PM

think about it, both trains move at the same speed, presuming they both need 5h. so let&#39;s say they&#39;re both doing 50mph(unlikely, but just an e.g.).

now if you ever had physics then you&#39;d know that object move faster when you move towards them while they move towards you and so the speed ads up.
this means the trains going from b to a are doing 100mph. so their going doubled as fast but still need 5h. you&#39;ll meet a train every half an hour.

dwightfry
02-12-2003, 05:59 PM
Originally posted by smellycat@12 February 2003 - 18:46
Assuming the trains from A and B start at the same minutes past the hour.

When you start on your journey, the train from B would have arrived.
You haven&#39;t passed it so it doesn&#39;t count.
An hour later and you would have been past by 1 train
Another hour later and you would have been past by 1 train
Another hour later and you would have been past by 1 train
Another hour later and you would have been past by 1 train
Another hour later and you arrive at the station. The train is just about to pull off.
You haven&#39;t passed it so it doesn&#39;t count.

Total Number of trains passing you = 4

Can you guys be in charge of calculating my wages? :D
That was my first thought too, but then I decided to include the train that is leaving and the train that is coming in. I figuared by &#39;pass&#39; he meant how many you would &#39;see&#39;.

I wish he would tell us if anyone is right yet?&#33;?&#33;?&#33;?&#33;?

PersianBulldog
02-12-2003, 09:21 PM
Oh dear.. So many answers so few of them correct.. :rolleyes:

Listen:

My train leaves 12 o&#39;clock..
At the moment that I leave the trainstation, I can see the train that left B 7 o&#39;clock.
One hour later, I&#39;ll see the train that left 8 o&#39;clock.. I&#39;ll wait an hour and I see the train that left B at 9 o&#39;clock.. One hour of stillness, until I see the 10 o&#39;clock train. At the last hour of my trip, I see the train that left 11 o&#39;clock. Since a train leaves the station just as I arrive, I see that one too.. I have now seen 6 trains.. Correct me if I&#39;m wrong.. This is my maths homework for tomorrow.. =)

Can&#39;t see in any other way.. ;)

TClite
02-12-2003, 09:28 PM
I thought boolean algebra was hard..lol

ooo
02-12-2003, 09:33 PM
im too lazy to think, doing my biology homework rite now, on meiosis... ah wat fun.... mitosis n meiosis...

question number 4)
explain the role of crossing - over in ensuring genetic variation?

5) describe the primary differences between spermatogenesis and oogenesis.

dwightfry
02-12-2003, 09:44 PM
Originally posted by artmaster88@12 February 2003 - 18:58

think about it, both trains move at the same speed, presuming they both need 5h. so let&#39;s say they&#39;re both doing 50mph(unlikely, but just an e.g.).

now if you ever had physics then you&#39;d know that object move faster when you move towards them while they move towards you and so the speed ads up.
this means the trains going from b to a are doing 100mph. so their going doubled as fast but still need 5h. you&#39;ll meet a train every half an hour.
ummm.....no

The trains going from B to A, in your explanantion would still be going 50 mph. If these 2 trains were to collide, then yes, the collision would be equivalent to 1 train going 100 mph and crashing into a wall.

smellycat
02-12-2003, 10:10 PM
Changed my mind.

I start off at 6.0am.

Arriving at the station is the 1.0 am. Also on the track travelling toward me is the 2.0 am, 3.0 a.m., 4.0 a.m
5.0 a.m and the 6.0 a.m is just pulling off.

During the trip I pass all those trains.

When I arrive at the station it is 11.0 am

In that time, I also would have passed the 7.0 a.m, 8.0 a.m, 9.0 a.m and the 10.0 a.m.
The 11.0 a.m is just pulling off.

If we use the semantics of see = pass then I would have passed 11 trains.

ooo
02-12-2003, 10:14 PM
ummm okay...? we got a genusis here... n a bad speller (ME bad speller)

zdog
02-12-2003, 10:22 PM
Ok, I&#39;ve read the questions and have a question that might help me figure this one out. You have stated that a train leaves station B every hour although you haven&#39;t stated how long the train leaving station B takes to reach station A. Am I to suppose that trains leaving from both stations travel at the same speed???

Blue_Nose
02-12-2003, 10:23 PM
If the journey takes 5 hours Then no matter how hard you try to
make it hard, the fact is that you will pass 5 trains (and you will pass
each one every hour no matter how fast you are travelling)

Unless the trains coming the other way are on the same track,
in which case you will see only one <_<

dwightfry
02-12-2003, 10:26 PM
Originally posted by Soul814@12 February 2003 - 23:14
ummm okay...? we got a genusis here... n a bad speller (ME bad speller)
actually, we all act smart, but smelly cat is the only one that got it right I think.

VB
02-12-2003, 10:31 PM
A1 leaves 6:00 arrives 11:00 at B

B1 leaves 1:01 arrives 6:01 at A
B2 leaves 2:01
B3 leaves 3:01
B4 leaves 4:01
B5 leaves 5:01
B6 leaves 6:01
B7 leaves 7:01
B8 leaves 8:01
B9 leaves 9:01
B10 leaves 10:01
B11 leaves 11:01

So A1 will see B1-B10

dwightfry
02-12-2003, 10:36 PM
That&#39;s assuming that train b1 leaves at 1:01. If it leaves at exactly 1:00 then the answer would be either:

9 = you don&#39;t count the train that has stopped right when you started and the one that starts when you stop

or

11 = you do count them

I only bring this up because questions like these usually are assumed to have the trains leave at the same time.

depending on the actual wording of the problem, 9, 10, or 11 could be right.

Blue_Nose
02-12-2003, 10:37 PM
Originally posted by Paul@12 February 2003 - 23:31
A1 leaves 6:00 arrives 11:00 at B

B1 leaves 1:01 arrives 6:01 at A
B2 leaves 2:01
B3 leaves 3:01
B4 leaves 4:01
B5 leaves 5:01
B6 leaves 6:01
B7 leaves 7:01
B8 leaves 8:01
B9 leaves 9:01
B10 leaves 10:01
B11 leaves 11:01

So A1 will see B1-B10
That assuming that their are already trains on their way I reckon
its just as safe to assume there not.

zdog
02-12-2003, 10:38 PM
Blue Nose, I would have to disagree with your statement, time is a variable, the time taken to travel from one point to another depends on the speed and the distance to be traveled. for eg. if you are flying from NY to Chicago in a 747 it will take you less time compared to if you were flying in a Cesena. The distance that you are traveling doesn&#39;t change but the speed at which you are traveling results in the time taken to cover the same distance. If both trains were to be travelling at the same speed then my answer would have to be 6. There are a lot of ways to contradict my answer, for eg, the trains might not be visible,( the tracks might be far apart or ther might be some obsticle in the way that would pervent you from viewing the train on the opposite track) hence you might say that i never did pass any trains, if both trains travel on the same track then there will be a head-on collision and you will not pass any trains. Unless all the details are clearly stated there is no correct answer as one different people might make different assumptions.

smellycat
02-12-2003, 10:40 PM
If we assume it&#39;s British Rail then he&#39;d be lucky to see 1. :D

Actually, he&#39;d be lucky to even leave. :lol:

avtarofdeath
02-12-2003, 10:58 PM
Someone mentioned physics earlier and that would be on the right track because your speed adds up...so you would see a different amount of trains depending on the speed of your train and the trains departing from the other station...my guess would be if 50 mph is the speed of both trains then you would see 20 or 25 trains.

smellycat
02-12-2003, 11:04 PM
Edit: Removed gibberish

ugluk
02-12-2003, 11:14 PM
Smellycat and Paul are correct. and as for counting the trains at A and B you probably should not. since you don&#39;t pass them&#33; so then the answer is 9.

PersianBulldog
02-13-2003, 07:58 PM
I asked the teacher today, and she said that the real answer is 11.. So congrats Smelly Cat&#33; http://www.webforum.nu/images/wfstandard/smilies/bire.gifhttp://www.webforum.nu/images/wfstandard/smilies/beergrin.gif