Author Topic: Riddles  (Read 15278 times)

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Offline Paddy

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Re: Riddles
« Reply #30 on: December 17, 2010, 01:01:26 am »
Fester, I've done the sums again and I'm convinced I'm right. Although I agree it is a surprisingly small number.

Yorkie

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Re: Riddles
« Reply #31 on: December 17, 2010, 08:06:33 am »
Of course Paddy is almost correct!   It IS a small number.

The Circumference of a Circle is Pi x Diameter.  We do not need to know the diameter as we do know that we are increasing it by 1 inch.  Therefore the extra length needed is Pi x 1inch  which equals 3.142 inches.

Seems ridiculous but it is absolutely true.  Pddy's mistake is he used radius instead of diameter.  (Area of a circle is Pi x R2

Here is the maths

24.000 miles = 1,520,640,000 inches.  Therefore diameter = that divided by 3.142 which equals 483,971,992.4 inches

Increase diameter by 1 inch gives 483,971,993.4 then x 3.142 gives 1,520,640,003.142

Extra length  3.142 inches!   Well done Paddy- you're the closest - 2 Brownie Points for the effort!
« Last Edit: December 17, 2010, 08:09:26 am by Yorkie »


Offline Merddin Emrys

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Re: Riddles
« Reply #32 on: December 17, 2010, 08:39:42 am »
I'm still not convinced that its only 3.142"

if I have a 10" diameter sphere then the circumference is 31.42"
and if I add 0.5" to the radius and have a diameter of 11" then the circumference is 34.562" which gives an increase of 3.142"

with a 10 foot sphere (120") add 1" to the diameter and the circumference becomes 380.182" which gives an increase of
3.142"  :o 

I've just prooved you right yet i'm still not convinced  _))*
A pigeon is for life not just Christmas

Offline DaveR

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Re: Riddles
« Reply #33 on: December 17, 2010, 10:21:20 am »
A very minor, simple and relevant riddle:

Why is it pointless to grit roads with rock salt when the temperature is below -9°C?

Offline Merddin Emrys

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Re: Riddles
« Reply #34 on: December 17, 2010, 10:25:15 am »
A very minor, simple and relevant riddle:

Why is it pointless to grit roads with rock salt when the temperature is below -9°C?

because the water will freeze even with the salt in it at that temperature
A pigeon is for life not just Christmas

Offline DaveR

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Re: Riddles
« Reply #35 on: December 17, 2010, 10:34:55 am »
Yes. Rock salt works by lowering the freezing point of water to -9°C, so if temperatures fall further, it will not work.

http://chemistry.about.com/cs/howthingswork/a/aa120703a.htm

Yorkie

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Re: Riddles
« Reply #36 on: December 17, 2010, 10:59:14 am »
Thats why they put grit with it so one finishes with something like sandpaper even if it does not thaw. 

Offline Merddin Emrys

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Re: Riddles
« Reply #37 on: December 17, 2010, 02:33:17 pm »
here's a riddle,

A cowboy rides in to town on Wednesday, books into a hotel, stays one night and leave on Wednesday. How did he do it?
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Offline Quiggs

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Re: Riddles
« Reply #38 on: December 17, 2010, 02:44:39 pm »
The Hotel straddles the International date line, he goes in one end but departs at the other.   ;)
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Offline Merddin Emrys

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Re: Riddles
« Reply #39 on: December 17, 2010, 03:02:04 pm »
good guess, but wrong  ;D
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Offline Michael

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Re: Riddles
« Reply #40 on: December 17, 2010, 03:27:52 pm »
His horse was called "Wednesday"   Mike

Offline Merddin Emrys

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Re: Riddles
« Reply #41 on: December 17, 2010, 04:29:58 pm »
well done Mike  &well&
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Offline Michael

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Re: Riddles
« Reply #42 on: December 17, 2010, 05:32:47 pm »
I DON'T BELIEVE IT!!!!  I dont think I have ever got one of the quiz questions correct

Yorkie

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Another Mathematical one.
« Reply #43 on: December 17, 2010, 07:19:43 pm »
  Bags and Beads
 
You are given 5 bags. There are 10 beads in each of the bags. In four of the bags, the beads each weigh 10 grams.  In the remaining bag,  each bead  weighs only 9 grams. All the bags and beads look identical. You must  find out which bag has the lighter beads. The problem is that all the bags look identical and all the beads look identical. You can use a scale, but it has to be a single-tray scale, not a two-tray balance scale.  Also, you may use the scale only once. How can you find out which bag has the lighter beads?

 )*)&

Offline JasonW

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Re: Riddles
« Reply #44 on: December 17, 2010, 07:32:58 pm »
Place all the bags on the scale at the same time.
Remove each bag one at a time.
The heavier bags will lower the total weight by 100g when it is taken off the scale
The lighter bag will only affect the total weight by 90g