Andy Murray vs Joao Sousa, Thursday, Estimated time - 3:30pm BST - Discuss the match
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Riddles

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I just got the idea from a friends magazine she is reading.

Post your answers in Spoilers so it doesn't deter others guessing.  This is how to post a spoiler (missus the spaces) for those who don't know how its done.

[ spoiler ]*Answer*[ /spoiler ]


Riddle:

When asked how old she was, Mary replied:
‘In two years, I will be twice as old as I was five years ago’
How old is she?

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 she's Spoiler:
12.
[ Last edit by nkp2 April 28, 2008, 01:18 PM ] IP Logged
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Oh i see. Oh well. Sorted.
[ Last edit by nkp2 April 28, 2008, 01:18 PM ] IP Logged
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Who's supposed to ask next, Neil? I'll ask anyway (its quite complicated, so if you don't understand it, blame me!):

A man enters a hotel with a thousand rooms, numbered from 1 to 1000, and goes round opening all the doors (1000 doors). He then closes the doors of every second room (that is, room nos. 2, 4, 6 etc.). Then he goes to every third room and if he finds it open he closes it and if he finds it closed he opens it. Then every fourth room, then every fifth etc. etc., until every thousandth room. (of course, from after he does every 500th room, he's only doing one door each round!)

The question is, how many doors are left open at the end?
The answer can, and should be, worked out without resorting to going through it manually, so don't answer if you just did that!
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Spoiler:
500?
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Nope! There is a nice simple (but quite hard to think of) reasoning behind the answer, and you will almost definitely not guess the answer.
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OH hang on..... is it not just... (does quick count)..... Spoiler:
 169


Never mind I think that's ********...  lol
[ Last edit by nkp2 April 28, 2008, 02:30 PM ] IP Logged
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The only other thing i can think of is..... Spoiler:
 32
[ Last edit by nkp2 April 28, 2008, 02:40 PM ] IP Logged
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That last answer is so close, you probably got there with  the right reasoning, just made a small mistake in your calculation. What was your reasoning, or did you just go through the first few doors manually?
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I miscalculated. I meant to say Spoiler:
 31
if my reasoning is correct.
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Yup, thats right! Whats your reasoning?
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Spoiler:
 all the squares because they are the only doors to get visited an odd number of times [/spoier]
[ Last edit by nkp2 April 28, 2008, 02:58 PM ] IP Logged
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Very good! I'm impressed you got it so quick. It took me basically a whole day thinking about it, on and off, to get it, and i think maths is my best subject.

Do you want to give a riddle (i could ask another one)?
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 A black dog is sleeping in the middle of a black road that has no streetlights and there is no moon. A car coming down the road with its lights off steers around the dog. How did the driver know the dog was there?
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Very good! I'm impressed you got it so quick. It took me basically a whole day thinking about it, on and off, to get it, and i think maths is my best subject.

Do you want to give a riddle (i could ask another one)?


Maths IS my best subject lol
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