|
|
Go to page [Previous] 1~2 | ||||||||||
Edith Regular user Germany 131 Posts |
Ok guys, you are just thinking way to complicated...
I would go the 2km straight to the stream (jump up the ferry or have my own boat there) then get off the stream right under my grandma's house and walk 3km straight up to her. That leaves me with 5km of my own way to walk. So MY way is only 5km whereas the ferry's way might be longer but who cares about some machine? Edith |
|||||||||
Nir Dahan Inner circle Munich, Germany 1390 Posts |
Edith
I am afraid that on this particular day you ran out of fuel, so you would have to paddle yourself or solve the puzzle... |
|||||||||
mike paris Regular user 179 Posts |
Is the answer 5 km?you go 2 km south then 3km north, I am assuming the river was at the north pole.
|
|||||||||
TomasB Inner circle Sweden 1144 Posts |
Mike, and how do you measure the distance that grandma is 12 km to the west of you? You make a great point though that these problems probably should be in cartesian coordinates.
/Tomas |
|||||||||
mike paris Regular user 179 Posts |
(Cartesian Coordinates? sorry I don,t know what that is). If you are close to the north pole but not on top,the river will be going east to west below you (remember its a globe), and the position of the grandma is 12 km to the west of you,so if you went 12 km west that would be true (maybe it would also be 12 km to the east to get to her house), she would also be north of you by going over the top of the north pole to get to her house.
|
|||||||||
TomasB Inner circle Sweden 1144 Posts |
So the circumference of the disc at the level of your house is 24 km? Half way round this circle and one km upwards is your grandma's house? Now, how do you calculate the distance between your house and grandma's house when you go over the north pole? My guess is that you'll have to make a lot of assumtions regarding the shape of Earth and that they will still be wrong.
If on the other hand you live where the circumference of the disc is 12 km and your grandma lives one km north of you, I guess it holds and is a quite fun solution to the problem as stated. Actually that is what I thought you meant at first. /Tomas |
|||||||||
mike paris Regular user 179 Posts |
Thomas,if grandma is (12 km west of you + 1 km north fact) (bear in mind if you used a compass the compass would read west),that would make her 3 km north of the river FACT,i assume that she is at the north pole which means YOU are 1 km from the north pole, and so 2km south,2 km,s north plus 1 km to her house equals 5km.
You don,t need to calculate the distance over the pole because there are no other measurments put forward, so I reckon she is on top of the north pole. Its only a guess but seems a lot less than 12+1+2? km,s, Mike |
|||||||||
TomasB Inner circle Sweden 1144 Posts |
I see. If you consider the earth flat around the north pole the circumference of that disc would be 2pi*1 km. Since the earth isn't flat there the actual circumference must be smaller than 2pi km. 2pi km is still less than 12 km, so she must be living closer to you than 12 km in the east/west direction.
But I still think you bring out a good point. We should specify that these people live in Flat Land. Belives, /Tomas PS No answers to the updated problem where Ray walks half as fast carrying water? |
|||||||||
magicjohn2278 Special user Isle of Man UK 544 Posts |
I'd head for a point 12km west and 3km south of the stream, until you get to the stream, then walk straight to Grandma's. That way I don't have to calculate that I must hit the stream at a point 4.8km west of my starting point!
|
|||||||||
mike paris Regular user 179 Posts |
Thomas ,i don,t understand much about pi, but lets suppose I am right ,grandma is on top of the north pole, you are 1km south of her, if you have a compass and it points north to the north pole, BUT you go west for 12 km (grandma lives 12 km west + 1 km north)stop then go 1 km north you are at her house (try this out on a ball or globe), which is the same as I said before, go south 2km, go north 2km to yout house then go the 1 km north to the north pole (her house) remember it is a puzzle and it is the only place on the earth (apart from the south pole with figures reversed) that this would work.Can anyone come up with another solution?
|
|||||||||
TomasB Inner circle Sweden 1144 Posts |
Yes, your solution works, Mike, but is contrieved since you will pass your own house while measuring that westward path to grandma. There are infinitely many places on a globe where you'd beat 13km.
I do think your solution provides the minimum distance on any place on a sphere with a sufficiently big enough radius. It'd be a fun problem to find some place that beats 5 km. Another place that gives the same minimum distance would be where the disc has a circumference of 12 km so you end up at your own house after going 12 km west and grandma lives 1 km north of you. Yet another place to consider is where the circumference is 6 km but then you are closer than 1 km to the pole so that won't work. Not sure if there are any other places that'd give 5 km or less (apart from the south pole). /Tomas |
|||||||||
mike paris Regular user 179 Posts |
Thomas ,try this,with a compass draw a 3"radius circle (this represents the stream 3 km from the north pole, now mark a 1" semi-circle,this marks the son,s house at one end (2" away from the stream)and the other end of the 12km to the westerly route, now where the point of the compass goes,mark that as the grangma,s house. you have a scale of 1" equal to 1 km, I am not sure how the measurements will work out but remember, on a globe a N/S compass will always point to north so as you go around a globe, the north of a compass will always point to the same spot.
|
|||||||||
idris New user St. Louis, MO 38 Posts |
Mike,
The point of the puzzle is that your grandmother lives 12km west of you as well as 1km north. If she lives at the north pole then she isn't 12km west of you, but due north of you. Jerry PS. And no, I still haven't figured out a clean way to determine the carrying water version. (Grin)
Jerry
|
|||||||||
mike paris Regular user 179 Posts |
Idris, she can still be (12km west of you +1km north),If he had said she was (12km west of you)1km north,then that would have been different,maybe Nir should join in and if I am wrong to say so.Then I can start thinking of an alternative solution.
|
|||||||||
mike paris Regular user 179 Posts |
Put snow or ice in the bucket,let it melt when you get to grandma,s.
|
|||||||||
The Magic Cafe Forum Index » » Puzzle me this... » » Visiting grandma (0 Likes) | ||||||||||
Go to page [Previous] 1~2 |
[ Top of Page ] |
All content & postings Copyright © 2001-2024 Steve Brooks. All Rights Reserved. This page was created in 0.01 seconds requiring 5 database queries. |
The views and comments expressed on The Magic Café are not necessarily those of The Magic Café, Steve Brooks, or Steve Brooks Magic. > Privacy Statement < |