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Alison Kiddle

Works at University of Cambridge

128 followers|132,376 views

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### Alison Kiddle

Shared publicly -This is one of our latest problems. I'm particularly proud of the animated egg dropping, although I've had complaints that it doesn't seem to be behaving as an object falling under gravity should.

Enjoy!

https://nrich.maths.org/10870

Enjoy!

https://nrich.maths.org/10870

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### Alison Kiddle

Shared publicly -Quite a lot of nice maths can be explored from this starting point. Would love to know what questions it prompts for other people!

### Alison Kiddle

Shared publicly -So here's the latest problem I've been playing with. You have a set of numbered cards and a set of blank cards. Here's a process - choose any two of your numbered cards, write their (positive) difference on one of your blank cards, and replace the two original cards with your new card. (So if you started with n cards, you now have n-1 cards.)

Keep doing this until you only have one card left.

The original problem that was posed to me was as follows: if you start with cards numbered 1-100, prove that when you have one card left it has an even number on it.

Once I'd proved that, I played around a bit. Here's some questions I enjoyed exploring: What sets of cards could I start with that guarantee finishing with an even number? What even finishing numbers are possible with the 1-100 set in the original problem? Given a set of cards with the numbers 1-n, what could the last card have on it?

Would love to hear any other interesting questions that occur. And of course, always interested to hear other people's solutions too!

Keep doing this until you only have one card left.

The original problem that was posed to me was as follows: if you start with cards numbered 1-100, prove that when you have one card left it has an even number on it.

Once I'd proved that, I played around a bit. Here's some questions I enjoyed exploring: What sets of cards could I start with that guarantee finishing with an even number? What even finishing numbers are possible with the 1-100 set in the original problem? Given a set of cards with the numbers 1-n, what could the last card have on it?

Would love to hear any other interesting questions that occur. And of course, always interested to hear other people's solutions too!

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I don't usually bother, but I suppose you're used to putting hashtags on things 'cos you post everything on that other site rather than here :P

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### Alison Kiddle

Shared publicly -I'm tired at work today, because of +Ian Glover who sent me this the other day. Pleased to say I solved it at last, slightly disappointed that my crazy brain decided 1:30am was the best time to work on it!

Also it's got me thinking about the bloody blue-eyed islanders again...

http://www.thebigquestions.com/2013/10/08/tuesday-puzzle-3/

Also it's got me thinking about the bloody blue-eyed islanders again...

http://www.thebigquestions.com/2013/10/08/tuesday-puzzle-3/

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### Alison Kiddle

Shared publicly -Warning: contains me.

New video now online to show you how to play power countdown http://nrich.maths.org/6448

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Hey, that hadn't occurred to me! Neat!

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### Alison Kiddle

Shared publicly -I made a 'gingerbread' cottage, out of felt instead of gingerbread. It has lights and is shiny. If you want to make one, I made instructions: https://docs.google.com/document/d/1yJVD2Sb4V6y4KFBkD8CIrlTeGcnU-z0Eu9d3vHUwqW0/edit?usp=sharing

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### Alison Kiddle

Shared publicly -Like animated gifs? Then you're going to LOVE our latest collection of resources... https://nrich.maths.org/10791

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### Alison Kiddle

Shared publicly -Bag based on tutorial at http://www.craftster.org/forum/index.php?topic=51187.0#axzz2Wt7rTtyj. Hoping to make another one soon but this time get the patches a bit neater. A rotary cutter and mat would be useful I think, as the fabric was quite hard to cut in a straight line. The method for making a lined reversible bag was very straightforward once the patchwork pieces were joined though, and I reckon I could have a go at some other geometric designs for the patchwork. As long as the finished piece of fabric is a rectangle, I can adjust the dimensions of the lining and finish off as per the instructions.

Had great fun making this, and pleased with how it's turned out, as I think it may be my first piece of machine-sewing in 2013 :-o

Had great fun making this, and pleased with how it's turned out, as I think it may be my first piece of machine-sewing in 2013 :-o

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Story

Introduction

Former maths teacher now working for http://nrich.maths.org, when I'm not doing maths/education related stuff I'm probably knitting, sewing or crocheting.

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Gender

Female

Work

Employment

- University of Cambridgepresent

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