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SpeedRacer

Brain teaser brainlock

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This is driving me nuts. Normally I'm good at these things, but I'm experiencing a brainlock and I just don't know how to approach this. How do you go about figuring this one out:


Each day a man's wife meets him at the railroad station and drives him home. One day he arrives at the station an hour early and begins to walk home along the road his wife always takes. She meets him en route and takes him the rest of the way home. Had he waited at the station, she would have picked him up exactly on time. As it turned out, he reached his home twenty minutes early. How long did the man walk?
:S
Speed Racer
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Each day a man's wife meets him at the railroad station and drives him home. One day he arrives at the station an hour early and begins to walk home along the road his wife always takes. She meets him en route and takes him the rest of the way home. Had he waited at the station, she would have picked him up exactly on time. As it turned out, he reached his home twenty minutes early. How long did the man walk?
:S



didn't he walk the distance she would normally drive in 10 minutes? (ie. a 10 minute drive from the station)

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Might just be being silly - but surely you need more information
all you know is that during a 40 minute period a man travelled an unspecified total distance, he walked an unspecified distance at an unspecified speed, he was driven an unspecified distance at an unspecified speed and then asked how long he walked for - thats an equation with about 5 variables!

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This may be a semantic puzzle.

"He walked all the way until she picked him up." That's how "long" he walked. The question did not ask how "far."

It's like asking how many people are dead in a cemetery. The answer is, "All of them."


My wife is hotter than your wife.

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no, there is an answer (in minutes) to this. I looked it up, I just can't figure how it was reached.

And the answer cannot be forty minutes:

Most days the man takes x minutes to make it home. Today it took him x + 40 minutes because he had to walk part of the way. But he cannot have walked for forty minutes and then gotten a ride the rest of the way and had it still take x minutes to get home, because by walking part of the way he would have reduced the distance between himself and his home.

So from the time he got picked up, it would take him less than x minutes to get home. So he must have been walking for longer than forty minutes.
Speed Racer
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Okay. Hypo.

It takes ten minutes to drive from station to home. It takes an hour to walk from station to home. Wife always picks him up ten minutes after he exits the train. Drives back.

So, if he normally exits train at 5:00, and she picks him up at 5:10, he arrives home at 5:20.

Today, he arrives at 4:00, walks for one hour. Wife leaves at 5:00 to take him from the sidewalk to the driveway. He gets home at 5:00. Normally it would have been 5:20. he saved twenty minutes.

Does that work?


My wife is hotter than your wife.

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no, there is an answer (in minutes) to this. I looked it up, I just can't figure how it was reached.

And the answer cannot be forty minutes:

Most days the man takes x minutes to make it home. Today it took him x + 40 minutes because he had to walk part of the way. But he cannot have walked for forty minutes and then gotten a ride the rest of the way and had it still take x minutes to get home, because by walking part of the way he would have reduced the distance between himself and his home.

So from the time he got picked up, it would take him less than x minutes to get home. So he must have been walking for longer than forty minutes.



X=20 minutes (hence being home 20 min earlier than usual)
x(20)+ y(60) amount of time arrived early
20+60=80
she met him 1/2 way
80/2=40 min.

I'm definitely not a math genious... but that what I was thinking....:S

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um, no.

answer has to be in How many minutes he spent walking. (also the lag time between exiting the train & getting picked up on a normal day is irrelevant. we might as well assume that on a normal day he gets picked up as soon as he exits the train)
Speed Racer
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30 minutes walking?!

So. Let's see. We know it took him forty minutes longer than normal to get home. If he spent thirty of those minutes walking towards his home, (thereby decreasing the distance his wife would have to drive him), then how could it be that from the moment she picked him up on the road, it still took him his usual full-distance time, plus an extra ten minutes to get home?

Logically the answer must be that he walked for longer than forty minutes, but I don't know how to set up the equation for that.
Speed Racer
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30 minutes walking?!

So. Let's see. We know it took him forty minutes longer than normal to get home. If he spent thirty of those minutes walking towards his home, (thereby decreasing the distance his wife would have to drive him), then how could it be that from the moment she picked him up on the road, it still took him his usual full-distance time, plus an extra ten minutes to get home?

Logically the answer must be that he walked for longer than forty minutes, but I don't know how to set up the equation for that.



Editing:


So, 2x results in a difference of -20.

Y (the time he walked) is (-60 minus -20) minus (x minus -20)

I'm _pretty_ sure I have this right.
"I encourage all awesome dangerous behavior." - Jeffro Fincher

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This is driving me nuts. Normally I'm good at these things, but I'm experiencing a brainlock and I just don't know how to approach this. How do you go about figuring this one out:



Er...by going to a forum and making everyone else now be consumed by your brainteaser? So not fair.

All I know is the answer is 50 minutes. Don't know how. Don't know why. But that's the answer. I did my research.

That is all.


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Definition of variables:
Tt = Normal time to get home
Tw = Amount of time he walked
Td = Amount of he was in the car

First look at the time the the wife traveled:

She traveled 2*Td
She also traveled Tt+Tt-20

2Td= 2Tt-20
Td = Tt-10

Now lets look at the time he spent traveling

He traveled Tw+Td
He also traveled 60 + Tt-20

Tw+Td = Tt+40
Tw+Tt-10 = Tt+40
Tw = 50 minutes

I think this makes sense:)

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This is driving me nuts. Normally I'm good at these things, but I'm experiencing a brainlock and I just don't know how to approach this. How do you go about figuring this one out:


Each day a man's wife meets him at the railroad station and drives him home. One day he arrives at the station an hour early and begins to walk home along the road his wife always takes. She meets him en route and takes him the rest of the way home. Had he waited at the station, she would have picked him up exactly on time. As it turned out, he reached his home twenty minutes early. How long did the man walk?
:S



Since he AND HIS WIFE saved 20 minutes, it follows that the wife saved 10 minutes on the outbound trip and 10 minutes on the return trip. So the time at which she met him was 10 minutes earlier than she would normally have been at the station.

Since he started walking 60 minutes before she would have met him at the station, she met him after he had been walking (60 - 10) minutes = 50 minutes after he left the station. QED.
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Oh, you beat me to the punch with the explination. I've got to learn to type faster.

~Cindy~
Quantum materiae materietur marmota monax si marmota monax materiam possit materiari?
Spelling and grammar errors are left as an exercise for the reader.

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