SPAMming along...

Posted by: CanukDenis

SPAMming along... - 02/28/13 02:18 AM

[Spam cans and you]>....................100 miles.........................>

-you are standing next to a pile of 5-ounce Spam cans (pork/ham mix!)
-these are sufficient in number to complete this puzzle!
-you wish to walk a distance of 100 miles (straight path)
-to keep up your strength, you need to eat a Spam can after each mile you walk
-you can carry a limit of 60 cans, no more

So first, you need to place a certain number of cans at certain mile points;
as example, you could walk 10 miles, leave 40 cans at that point, then return:
you will have eaten 20 cans during this trip, right?
NO, you CANNOT do stuff like walk 3/4 mile then eat 3/4 of a can:
you MUST deal with full cans at ALL times!!

What is the minimum number of cans that can be at the starting point?
Posted by: CCbomber

Re: SPAMming along... - 03/01/13 06:26 AM

236 cans think

1st trip
start with 60 cans, travel 8m, dump 44 cans, return

2nd trip
start with 60 cans, travel 8m, get 8 cans, travel 12m, dump 36 cans, turn around,
travel 12m, get 8 cans, return

3rd trip
start with 60 cans, travel 8m, get 8 cans, travel 12m, get 12 cans, travel 20m, dump 20 cans, turn around,
travel 20m, get 12 cans, travel 12m, get 8 cans, return

last trip
start with 56 cans, travel 8m, get 12 cans, travel 12m, get 12 cans, travel 20m, get 20 cans,
travel 60m (for a total of 100m)

number of cans consumed = 236
Posted by: CanukDenis

Re: SPAMming along... - 03/01/13 10:18 AM

Correct. Can be shown this way also (m8 = mile#8...):

3 return trips and 1 one-way trip from start to m8 : 236 - 8*7 = 180 cans at m8

2 return trips and 1 one-way trip from m8 to m20 : 180 - 12*5 = 120 cans at m20

1 return trip and 1 one-way trip from m20 to m40 : 120 - 20*3 = 60 cans at m40

All over...60 cans with 60 miles to go!