OK try this one on for size

GamerExpress

Banned
Aug 28, 2005
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You have a cylindrical can of the sort that baked beans are sold in. You want to fill it exactly one quarter full of water but you have no measuring instrument and the can is not graduated in any way (though you can scratch it yourself if you wish).
How should you proceed
 

DaShen

Lifer
Dec 1, 2000
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Poke a hole in the direct middle of the can, then poke another hole at the 1/4 and then fill to your heart content. It will drain to the 1/4.
 

Tommunist

Golden Member
Dec 1, 2004
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Originally posted by: GamerExpress
You have a cylindrical can of the sort that baked beans are sold in. You want to fill it exactly one quarter full of water but you have no measuring instrument and the can is not graduated in any way (though you can scratch it yourself if you wish).
How should you proceed

does it have to do with balancing the can on edge? with the water in it?
 

Tiamat

Lifer
Nov 25, 2003
14,068
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tilt the can so that the midway point and the lifted bottom corner form a line that is parallel to the table then fill. When the lip of the fluid fills to the half way point on the can (humans can view halves very easily) you have 1/4 can.

Or Akubi's method which is more clear.

Its all about right triangle trig in 2 of the 3 dimensions.
 

akubi

Diamond Member
Apr 19, 2005
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tilt the can and start filling with water until the water's top surface touches the bottom of the open face and top of the closed face. tilt it back straight. mark off the half way point. empty it if you choose, then tilt it and fill until water's top surface touches bottom of half-way circle you marked off, and the top of the closed face. you now have exactly 1/4.

disclaimer: will not work without gravity.
 

DaShen

Lifer
Dec 1, 2000
10,710
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Originally posted by: akubi
tilt the can and start filling with water until the water's top surface touches the bottom of the open face and top of the closed face. tilt it back straight. mark off the half way point. empty it if you choose, then tilt it and fill until water's top surface touches bottom of half-way circle you marked off, and the top of the closed face. you now have exactly 1/4.

disclaimer: will not work without gravity.

Dang, nice work
 

Tommunist

Golden Member
Dec 1, 2004
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Originally posted by: Tiamat
tilt the can so that the midway point and the lifted bottom corner form a line that is parallel to the table then fill. When the lip of the fluid fills to the half way point on the can (humans can view halves very easily) you have 1/4 can.

i think there is too much estimating there for it to count. if estimating halves is so easy the cutting the can in half 2 times would work just as well...
 

dullard

Elite Member
May 21, 2001
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Since many baked bean cans are ribbed, I'd count the number of ridges and then divide by four. ;)
 

EPCrew

Senior member
Jun 2, 2000
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Originally posted by: Tiamat
tilt the can so that the midway point and the lifted bottom corner form a line that is parallel to the table then fill. When the lip of the fluid fills to the half way point on the can (humans can view halves very easily) you have 1/4 can.


i think this is close. if you tilt the can so that the top, bottom corner is parallel to the open bottom corner, you'll have your halfway point when the water reaches the end. now put the can flat and mark the water level. that is your halfway point and repeat the first step using the halfway point.
 

Tommunist

Golden Member
Dec 1, 2004
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Originally posted by: akubi
tilt the can and start filling with water until the water's top surface touches the bottom of the open face and top of the closed face. tilt it back straight. mark off the half way point. empty it if you choose, then tilt it and fill until water's top surface touches bottom of half-way circle you marked off, and the top of the closed face. you now have exactly 1/4.

disclaimer: will not work without gravity.

that should do the trick...
 

GamerExpress

Banned
Aug 28, 2005
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Fill the can to over half full, and tip it so that the water runs out until it reaches just from the lip of the can to the edge of the base, as in the first figure.
Now the can is one half full. Tilt the can upright and mark it inside to show how far the water comes. Finally, tip out the water a bit at a time, until when tilted, the water goes from the mark you scratched to the edge of the bottom.

There you go.
 

Tiamat

Lifer
Nov 25, 2003
14,068
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Originally posted by: Tommunist
Originally posted by: Tiamat
tilt the can so that the midway point and the lifted bottom corner form a line that is parallel to the table then fill. When the lip of the fluid fills to the half way point on the can (humans can view halves very easily) you have 1/4 can.

i think there is too much estimating there for it to count. if estimating halves is so easy the cutting the can in half 2 times would work just as well...

thus my edit...
 

PingSpike

Lifer
Feb 25, 2004
21,758
603
126
eyeball it and dump then. I can't think of a situation where I'd need to make a precise measurement of an amount of water using only an empty bean can. If I'm trying to cool a nuclear reactor, I'll just go buy a measuring cup.
 

Ilmater

Diamond Member
Jun 13, 2002
7,516
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Originally posted by: Tommunist
Originally posted by: Tiamat
tilt the can so that the midway point and the lifted bottom corner form a line that is parallel to the table then fill. When the lip of the fluid fills to the half way point on the can (humans can view halves very easily) you have 1/4 can.

i think there is too much estimating there for it to count. if estimating halves is so easy the cutting the can in half 2 times would work just as well...
There's no estimating.