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Pole in lake

115 replies to this topic

#1 TEX

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Posted 02 July 2007 - 07:48 AM

There is a pole in a lake. One half of the pole is in the ground, another one third is covered by water and eight feet is out of the water. What is the total length of the pole in feet?
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#2 normdeplume

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Posted 02 July 2007 - 02:18 PM

48 Feet.

He's one big Pole.

There's a man walking to an Olympic village with a long stick under his arm. Security stops him and asks
'Are you a pole vaulter?'
The man replies ' Nine. I am German. But how did you know my name was Walter!'
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#3 knoxmic

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Posted 02 July 2007 - 02:25 PM

Surely it's 48 feet
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#4 trailblazer

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Posted 14 January 2008 - 03:54 PM

hmmmm.... methinks it's more than that.... Cos if 50% of pole is in the ground and 33% (one third) is in the water then only 17% is sticking out of the water. The eight feet represents 17% of the total length of the pole there fore the total length is 331 feet!
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#5 mindwarp

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Posted 14 January 2008 - 04:49 PM

hmmmm.... methinks it's more than that.... Cos if 50% of pole is in the ground and 33% (one third) is in the water then only 17% is sticking out of the water. The eight feet represents 17% of the total length of the pole there fore the total length is 331 feet!

I'm not sure what how you're performing your calculations, but using the percentage data, I was able to come up with 47 and a fraction.

How I [originally] calculated it:

x/2 + x/3 + 8 = x

x/2 + x/3 -x = -8

3x/6 + 2x/6 - 6x/6 = -8

-x/6 = -8

-x = -48

x = 48
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#6 Emapher

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Posted 06 February 2008 - 03:13 PM

1/2 Is in the ground-
1/3 (of what is not in the ground) is under water
8 ft. is out of the water.

I------------I----|----|----I
1/2 in the ground

I------------I----|----|----I 2/3 = 8ft
...........................8ft

If 2/3 = 8ft then the other 1/3 = 4ft

I------------I----|----|----I
............................12'

12' doubled - as half of the pole is in the ground- is 24'

I------------I----|----|----I
...............24'

Right??

Edited by Emapher, 06 February 2008 - 03:15 PM.

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#7 McSquid

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Posted 06 February 2008 - 04:02 PM

1/2 Is in the ground-
1/3 (of what is not in the ground) is under water
8 ft. is out of the water.

I------------I----|----|----I
1/2 in the ground

I------------I----|----|----I 2/3 = 8ft
...........................8ft

If 2/3 = 8ft then the other 1/3 = 4ft

I------------I----|----|----I
............................12'

12' doubled - as half of the pole is in the ground- is 24'

I------------I----|----|----I
...............24'

Right??

no,
1/3 (of what is not in the ground) is under water <--- that is your error. its 1/3 of the ENTIRE pole not just whats out of the ground.

{------------------------}[----------------]|--------| {ground} [water] |air| one - = 1ft

1/2 = 3/6
1/3 = 2/6
+________
5/6

meaning 1/6 = 8ft
8x6 = 48 ft.
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#8 niner

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Posted 06 February 2008 - 07:55 PM

hmmmm.... methinks it's more than that.... Cos if 50% of pole is in the ground and 33% (one third) is in the water then only 17% is sticking out of the water. The eight feet represents 17% of the total length of the pole there fore the total length is 331 feet!

8 / 0.17 = 47+

8 / 331 = 0.024169 = 2.4% not 17%
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#9 MattGreer

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Posted 06 February 2008 - 08:05 PM

The answer is absolutely 48 feet.

1/2 + 1/3 = 5/6

1/6*x = 8; where x = length of the pole

x = 48

Nice puzzle. I haven't manually added a fraction in a long time!
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#10 FirebirdVII1963

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Posted 06 February 2008 - 08:47 PM

I believe that the pole is only 12 feet long.
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