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April 20th, 2010, 05:45 AM   #1
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Crossing a desert (alternative)

You and your truck want to travel across a desert. You have calculated that all the provisions you need for one day's travel(fuel, food, etc.) can be contained in 1 'big box' and the truck can only carry 10 big boxes. There are no provisions available in the desert, but there is a limitless supply of Big boxes at the starting point.

How do you plan your journey, and how many days will it take you, in each of the following situations?

1. you know that the distance across the desert is exactly 12days travel

2. you know that the distance across the desert is exactly 20days travel

3. you know that the distance across the desert is exactly 100days travel

4. What should your strategy be if you did not know the size of the desert?
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April 20th, 2010, 10:32 AM   #2
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Re: Crossing a desert (alternative)

Quote:
Originally Posted by mathsman
How do you plan your journey, and how many days will it take you
I hope, you mean crossing the desert, not planning the trip.

Hm, challenging, in time, you can evaporate your pee to recycle the water, and you have some fertilizer to grow plants. Quite optimistic view though I think. In your truck, there is some shadow. You will need some fuel to drive your truck. Change of plan, not to cross the dessert?
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April 20th, 2010, 12:06 PM   #3
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Re: Crossing a desert (alternative)

yes "how many days will it take you to cross the desert" and i wish it was as simple as to say , I changed my mind lol.
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April 20th, 2010, 12:24 PM   #4
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Re: Crossing a desert (alternative)

In one of the big boxes, I would put an aeroplane to fly across the desert. That is, of course, when the vulcano on Iceland quitted erupting.
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April 20th, 2010, 01:10 PM   #5
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Re: Crossing a desert (alternative)

Quote:
Originally Posted by mathsman
1. you know that the distance across the desert is exactly 12days travel
Travel 2 days in, leave 2 days' of supplies, and return; then take 10 days' supplies, refuel at the the 2-mile mark, and cross. Time: 16 days.

Quote:
Originally Posted by mathsman
4. What should your strategy be if you did not know the size of the desert?
Sell big boxes, use the proceeds to buy a plane ticket.
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May 27th, 2010, 07:50 PM   #6
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Re: Crossing a desert (alternative)

20 Days: Bring 10 boxes -> Travel 3 days drop off 4 boxes -> Travel back pick up 10 boxes -> Travel 3 days drop off 4 boxes -> Travel back pick up 10 boxes -> Travel 3 days drop off 4 boxes -> Travel back pick up 10 boxes -> Travel 3 days drop off 4 boxes -> Travel back pick up 4 boxes -> Travel 3 days pick up 16 boxes -> Cross the damn desert.
Total Boxes: 44
Total Days: 44
Total Trips: 5
4(6d+10b) + 1(20d+4b)
Trip 1 10-3-(4)-3
Trip 2 10-3-(4)-3
Trip 3 10-3-(4)-3
Trip 4 10-3-(4)-3
Trip 5 4-3+(16)-17
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May 28th, 2010, 05:39 AM   #7
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Re: Crossing a desert (alternative)

Quote:
Originally Posted by Tonemurdock
Travel 3 days pick up 16 boxes
You can only carry 10.
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July 25th, 2011, 09:25 AM   #8
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Re: Crossing a desert (alternative)

okay, so we don't know the size of the desert, let's assume it's infinitely large (we have to do it for the worst condition), which is not possible, so we make it the largest possible, which will be the surface area of the earth minus the size of your truck (i am pretty sure you start at the edge of the desert), so you have to travel around the earth for that to happen, but you will be only moving for 0ft because you come back where you started, so what you do is rev the truck for 1 inch, so it will be in the desert, then move the truck forward 1 inch, so you are back where you started. if this method doesn't work. 2nd method is to dig through the earth... you get the idea.
but the problem with the truck is: How could a truck go through a desert without sinking into it? (i mean like wheels trap into the sand)
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