# Car Talk GPS Puzzle

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Have others tried to figure this one out:

http://www.cartalk.com/content/puzzler/tra...0906/index.html

Basically the GPS had an average speed higher than the maxium speed and it was working properly.

My intinal thought was it must be (brand deleted to avoid flames ) I also thought maybe it had to do with a time zone or daylight sayings times but could not figure out how that could get the result.

I think I might have finally figured it out-but I could be wrong. I will put what I think it is in a rely so you can go read the puzzle first.

Edited by myotis

Ok here is what I think but I am going to add some line breaks so you cannot see it when reading the first post.

High speed train in a tunnel

He flies over to England, turns on the GPS, drives to the high speed train going under the English Channel and rides it to the other side. Since you lose reception in the tunnel, the GPS would not record how fast the train was going in the tunnel (wickpidia says it goes 186 MPH). But when the GPS gets to the other side it draws a straight line from where it lost reception. So going fast in the tunnel gets counted in the trip average, but the high speed it traveled in the tunnel does not register on the maximum speed. Traveling for 28 hours is a bit of a problem - but they could have done most of it walking.

What do you think?

Well,

I don't think he flew the RV to London. I think the unit sat around for a week and the counter for the moving time overflowed and read a time smaller than the actual trip time. That would produce an incorrect average.

There is nothing in the puzzle indicating they were in the RV for any part of the trip. Your solution does not work for many reasons including the trip time was 28 hours so it could not be sitting around for a week.

Did you send an answer in to the show? I got an email back that is a riot.

Did you send an answer in to the show? I got an email back that is a riot.

Can you share???? I love those guys. They are hilarious.

Well the solution they gave does not work: They flew home in an airplane. They said they turned it off in Hawaii and when they got back home to AL they turned it back on. The problem is GPSs don't work that way. When you turn the GPS on at a new location, it does not calculate from the position you turned it off to your new position, it stats the calculations from when you turn it back on. After they told that solution, I reset my trip computer. Drove a little ways never going over 40. I took a screen shot right before I turned it off and noted the readings. Then I got on the Interstate and drove all the way going faster than 40. I got off the interstate and turned it back on. The readings remained the same as when I turned off the GPS. None of the time I had the GPS off was included in the calculations. If there solution was correct, I would have had the avg speed showing faster than the max speed.

They also said "there was nothing wrong with the unit or its calculations." Well even if the GPS operated the way they are assuming, the calculation would still be wrong as planes do not travel in a straight line. So the distance they traveled would have been greater than indicated. So the calculation would be wrong.

I still think the only way this is possible is a high speed train in a tunnel.

Did you send an answer in to the show? I got an email back that is a riot.

Can you share???? I love those guys. They are hilarious.

Thanks for sending us your answer to this week's Car Talk puzzler!

In case you were wondering, here's the process we go through to select each week's winner:

First, we have to be certain you have the correct answer. We start by sending your answer to Paul Murky, at Murky Research. Murky, working with our Statistician Marge Innovera, will place your puzzler answer in one of two heaps: "not even close" and "pretty much right."

Assuming it passes by Paul and Marge, your answer will then be zipped along to Central Processing, where it will be date and time stamped, and searched for attached currency. Next, it will be shipped electronically to our Correct Answer Verification Center, where our legions of lackeys once again search your answer for any lingering currency-- just in case someone at Central Processing missed it. Then, they make certain that your response fits the criterion we have established for correct answers.

Please note that since we're often unsure of what the right answer is ourselves, we have very wide latitude in determining what constitutes a correct answer. Incorrect answers, however, will be sent to the Jehovah's Witnesses for immediate inclusion in their mailing list.

Lastly, correct answers will be sent to Ms. Shirley Wright, who operates under the auspices of the Committee for Reviewing Answers to Puzzlers. There, operating under complete secrecy, Ms. Wright will pick a winner.

If your response is selected as this week's winning entry, we'll announce your name on the air. You'll also get a \$26 gift certificate to our Shameless Commerce Division-- but only if you catch us. Which means, what? You'll need to e mail us and mention that you heard your name on the air. If you're smart, you'll then trade your new Shameless Commerce Gift Certificate to an unsuspecting co-worker, for a cup of coffee and twenty-five cents. Why \$26? Simple. It used to be \$25... but we adjusted for inflation. About ten years ago. (No kidding.)

Cordially,

Tom and Ray Magliozzi

Click and Clack the Tappet Brothers

What happened to the latest puzzler? It's showing 2/2 as the current puzzler. What has the answer to this puzzle?

JetSkier

Where did you get the answer? Your post was on the 15th. When I checked the web site on the 16th, it said the answer would be made available at the end of the day. Also, it's not clear from your post what they saw after they threw the unit down the stairs and started picking up the pieces.

JetSkier

I listened. They did not see anything after throwing it down the stairs. I do not know why they don't have the answer posted. I emailed them pointing out they were wrong-but I do not think that is why it is not posted.

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