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richard barrett
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« Reply #3255 on: 00:29:21, 18-01-2008 » |
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It certainly has me puzzled at this point.
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George Garnett
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« Reply #3256 on: 00:38:40, 18-01-2008 » |
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Gosh! Well I've worked it out <smugsmugsmuggitysmug> which is a bit of a confidence booster after the cock up on the birthday thread earlier today.
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« Last Edit: 00:45:44, 18-01-2008 by George Garnett »
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MabelJane
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« Reply #3257 on: 00:43:03, 18-01-2008 » |
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Gosh! Well I've worked it out <smugsmugsmug> which is a bit of a confidence booster after the cock up on the birthday thread earlier today.
Don't tell me - I'd prefer to be kept in the dark! Quite enjoying the spookiness of it...  |
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Merely corroborative detail, intended to give artistic verisimilitude to an otherwise bald and unconvincing narrative.
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Evan Johnson
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« Reply #3258 on: 00:46:31, 18-01-2008 » |
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... don't look MJ ...
a = 10b + c; 10b + c - (b + c) = 9b; hence your number is a multiple of 9.
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richard barrett
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« Reply #3259 on: 01:37:34, 18-01-2008 » |
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Gosh! Well I've worked it out Strangely it was looking at that post of yours which seemed to make the answer somehow manifest itself to me. Now that IS spooky. |
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MabelJane
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« Reply #3260 on: 13:19:19, 18-01-2008 » |
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Here's another number trick which you clever mathematicians will no doubt be able to explain but it amazes me: Ask a friend to roll 2 dice but don't look at the numbers.
Tell her to:
Double one of the numbers.
Add 5 to it.
Multiply that answer by 5.
Add the second number.
Finally subtract 25.
The 2 digits will be those 2 numbers thrown at the start. |
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Merely corroborative detail, intended to give artistic verisimilitude to an otherwise bald and unconvincing narrative.
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increpatio
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« Reply #3261 on: 13:43:44, 18-01-2008 » |
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Here's another number trick which you clever mathematicians will no doubt be able to explain but it amazes me: Ask a friend to roll 2 dice but don't look at the numbers.
Tell her to:
Double one of the numbers.
Add 5 to it.
Multiply that answer by 5.
Add the second number.
Finally subtract 25.
The 2 digits will be those 2 numbers thrown at the start. Ah, right. That wasn't obvious to me initially either, for some reason except that it's just multiplying one number by ten and adding the other number to it. |
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MabelJane
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« Reply #3262 on: 13:59:15, 18-01-2008 » |
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except that it's just multiplying one number by ten and adding the other number to it.
But it's quite cleverly disguised isn't it? I still don't really understand it!  |
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Merely corroborative detail, intended to give artistic verisimilitude to an otherwise bald and unconvincing narrative.
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John W
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« Reply #3263 on: 17:01:30, 18-01-2008 » |
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Here's another number trick which you clever mathematicians will no doubt be able to explain but it amazes me:
Well MJ, you see, adding 5 and multiplying by 5 makes 25 which you take away at the end, that's one obvious bit sorted. And when you've doubled one number and then multiplied by 5 you essentially multipied the first number by 10, and then you added the other number..... See? basically you added 25, took it away, multiplied one number by 10 and added the other, no mystery really. |
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MabelJane
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« Reply #3264 on: 22:50:41, 18-01-2008 » |
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Here's another number trick which you clever mathematicians will no doubt be able to explain but it amazes me:
Well MJ, you see, adding 5 and multiplying by 5 makes 25 which you take away at the end, that's one obvious bit sorted. And when you've doubled one number and then multiplied by 5 you essentially multipied the first number by 10, and then you added the other number..... See? basically you added 25, took it away, multiplied one number by 10 and added the other, no mystery really. Thanks John - what I found puzzling is that the doubled number plus the 5 have both been multiplied by 5 simultaneously - and that it works whatever the number! My brain just isn't very good at numbers - I can understand the less able children at school having difficulties with maths. Perhaps that helps me to be very patient when I have to explain things over and over and over again! |
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Merely corroborative detail, intended to give artistic verisimilitude to an otherwise bald and unconvincing narrative.
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Milly Jones
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« Reply #3265 on: 23:09:52, 18-01-2008 » |
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This is my way.... Let the numbers be x and y. We'll choose x first 1) Double it 2x 2) Add 5 2x+5 3) Multiply by 5 10x+25 4) Add the second number 10x+25 +y 5) subtract 25 10x+y The adding 5 and subtracting 25 is just flim-flam to hide the fact that you've effectively multiplied the first number by 10 and added the second number. So if the starting numbers are five and seven then we end up with 5 times 10 - fifty - and seven. ie fifty seven. Any wiser?  |
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« Last Edit: 23:15:33, 18-01-2008 by Milly Jones »
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We pass this way but once. This is not a rehearsal!
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MabelJane
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« Reply #3266 on: 23:13:50, 18-01-2008 » |
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Merely corroborative detail, intended to give artistic verisimilitude to an otherwise bald and unconvincing narrative.
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Andy D
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« Reply #3267 on: 00:31:09, 19-01-2008 » |
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Try this one which I had in a book when I was a kid but it was on Mind Games on BBC4 a couple of years ago.
A man has 2 woman friends and he can't decide which he prefers. They live in opposite directions on his local railway so he decides to turn up at the station at random times and get on the first train which arrives, whichever direction it's going in. The trains run every ten minutes in both directions so he reckons that he'll see them both equally frequently but he ends up seeing one 9 times more frequently than the other. Why?
I found it really funny when they were running little wooden trains through toy stations on the programme, trying to work the answer out.
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George Garnett
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« Reply #3268 on: 00:54:47, 19-01-2008 » |
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Try this one which I had in a book when I was a kid but it was on Mind Games on BBC4 a couple of years ago.
A man has 2 woman friends and he can't decide which he prefers. They live in opposite directions on his local railway so he decides to turn up at the station at random times and get on the first train which arrives, whichever direction it's going in. The trains run every ten minutes in both directions so he reckons that he'll see them both equally frequently but he ends up seeing one 9 times more frequently than the other. Why?
I found it really funny when they were running little wooden trains through toy stations on the programme, trying to work the answer out.
You mean they might have done better to look at the train timetables instead?  |
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« Last Edit: 02:04:17, 19-01-2008 by George Garnett »
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time_is_now
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« Reply #3269 on: 00:59:16, 19-01-2008 » |
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Talking of train timetables, looks like at least two members have made it home! Hope a certain green one is also happy and nearly abed. I'm slightly in two minds as to whether I should work for a bit, or sleep now and hope to wake up early (past experience tells me this is a bad idea, but most of my comfort receptors seem to be keen on it). Either way, I could do with about 48 hours before tomorrow lunchtime, so I suppose I should tear myself away from this board and bid you all a wonderful Weirkend (I may see some of you tomorrow and/or Sunday). |
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The city is a process which always veers away from the form envisaged and desired, ... whose revenge upon its architects and planners undoes every dream of mastery. It is [also] one of the sites where Dasein is assigned the impossible task of putting right what can never be put right. - Rob Lapsley
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