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Melody

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यूजर का नामMelody
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Melody  11 Feb 2022
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Okay, I have finally got through all todays questions.
They all have good answers either from me or from one of you.
There are still 2 left from yesterday that I still intend to get back to
I should be able to do them tomorrow.

Helpers today included
Mighty, Sammy, Q-Who, Zamarronics, Kitty<3, one or more 'guests'
plus an WFT- an ocean of rice (who has been asked a clarification question which is not answered yet)
A really big thank you to all of you.

I was thanked by Echo and by a 'guest'. I appreciate this, i give my thanks in return.

-------------------------------------------------------------
When people post offensive material generally I think it is best to ignore it.
If it doesn't gain attention then the poster will probably decide it is not worth while and will either go away or will improve the quality of their posts.
That's my theory anyway.

Today someone used a post to bully another member. I don't think this sort of behaviour can or should be ignored or tolerated.
I told the person that this was not acceptable behaviour in this forum.
Last time this happened, Professor Lopez told the bully that their behaviour was not going to be tollerated and the bully just gave a little mouth full and left the forum.
I was very grateful to the Professor for her action.
I hope that my words will be equally effective. Of course, no one needs to leave the forum, they just may need to change their behaviour.
I would like you to support me, and let bullies know that that type of behaviour is not acceptable here.
Don't start calling them names or anything just be very sensible about it and show that you support the person being bullied and not the person who is doing the bullying.
If anyone has any good ideas on how to handle this sort of problem i would love you to speak up, or if you would just like to comment, that would be good too.

Thankyou all for making this forum so worth while.
Melody.
16 Jan 2014
 #1
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helpneeded105:

Train A leaves San Francisco at 8 am and heads towards Los Angeles, travelling 55 km/h. At the same time, train B leaves Los Angeles and heads towards San Francsico, travelling 65km/h. The distance between the two cities is 230 km. At what time will they pass each other?



hi 105,
You have yourself a good question here!
.................................. .............................................................230km..........55km/hr
.................................. San F -------distance=d------------------------------X-------------------------------------------------------------------------> Los Angeles
.................................. .............................................................230km..........65km/hr
.................................. San F <--------------------------------------------------X-----------------distance = d 2 = (230 - d)------------------------ Los Angeles

X is the point where the trains pass.

now, speed = distance/time
so, time = distance/speed
We need to know how long it will take them to get to X. We know that they will both take the same amount of time. Let the time taken be t

For the top train: t = d/55
For the bottom train: t = (230 - d)/65
therefore
d/55 = (230 - d)/65
After solving this we get d = 105 and 5/12 km This is the distance the top train has travelled
230 - 105 and 5/12 = 124 and 7/12 km This is the distance the bottom train has travelled.

Now, distance/speed = time
Top train: [105 and 5/12] / 55 = 1 and 11/12 hours = 1 hour and 55 minutes
Bottom train: [124 and 7/12] / 65 = 1 and 11/12 hours = 1 hour and 55 minutes

Good they have both taken the same amount of time to get to this point.
8am + 1hour and 55min = 9:55am
The trains will pass each other at 9:55am
15 Jan 2014