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  <resource>
  <id>7445</id>
  <path>/www/nrich/html/content/id/7445/</path>
  <resourceTypeID>6</resourceTypeID>
  <last_published>2011-02-01T00:00:01</last_published>
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&lt;mdoxml version=&quot;1.0&quot;&gt;&lt;br&gt;&lt;/br&gt;
If you&amp;#39;ve ever used Twitter you&amp;#39;ll know that you&amp;#39;re only allowed to write 140 characters in any one tweet. The team at Twilgo used this idea, combined it with a programming language (Logo) and set up a site for us where you can write instructions to design a mathematical picture, but only using 127 characters!&lt;br&gt;&lt;/br&gt;
 &lt;br&gt;&lt;/br&gt;
If you want to just get going, follow the link &lt;a href=&quot;http://twilgo.com&quot;&gt;here&lt;/a&gt; and come back to this page later to see what our challenges are for this month.&lt;br&gt;&lt;/br&gt;
&lt;br&gt;&lt;/br&gt;
&lt;h3&gt;Starting to use TWILGO&lt;/h3&gt;
&lt;br&gt;&lt;/br&gt;
For example, let&amp;#39;s say you wanted to mark out a square which has sides 10 units long.&lt;br&gt;&lt;/br&gt;
The first instruction will be to move forward 10 units. In Twilgo we write this as &lt;span style=&quot;font-weight: bold;&quot;&gt;FD 10&lt;/span&gt;.&lt;br&gt;&lt;/br&gt;
Then we have to turn through 90 degrees before we draw the next side. In Twilgo we write this as &lt;span style=&quot;font-weight: bold;&quot;&gt;RT 90&lt;/span&gt;.&lt;br&gt;&lt;/br&gt;
We need to do this four times to get back to the beginning so we could write:&lt;br&gt;&lt;/br&gt;
 &lt;br&gt;&lt;/br&gt;
&lt;span style=&quot;font-weight: bold;&quot;&gt;FD 10 RT 90  FD 10 RT 90 FD 10 RT 90 FD 10 RT 90&lt;/span&gt;&lt;br&gt;&lt;/br&gt;
 &lt;br&gt;&lt;/br&gt;
However, that uses a lot of characters so we can make it shorter by writing:&lt;br&gt;&lt;/br&gt;
&lt;br&gt;&lt;/br&gt;
&lt;span style=&quot;font-weight: bold;&quot;&gt;REPEAT 4 [FD 10 RT 90]&lt;/span&gt;&lt;br&gt;&lt;/br&gt;
&lt;br&gt;&lt;/br&gt;
That&amp;#39;s the general idea so now go to &lt;a href=&quot;http://twilgo.com/nrich/&quot;&gt;NRICHTWILGO&lt;/a&gt; and explore! Everything you need to know is in the HELP tab.&lt;br&gt;&lt;/br&gt;
 &lt;br&gt;&lt;/br&gt;
&lt;h3&gt;This month&amp;#39;s challenges:&lt;/h3&gt;
&lt;h4 style=&quot;font-weight: 400;&quot;&gt;If you would like to let us know how you got on with these, you can &lt;span style=&quot;font-style: italic;&quot;&gt;either&lt;/span&gt;&lt;/h4&gt;
&lt;p style=&quot;text-align: center;&quot;&gt;join Twitter and upload your designs into the gallery&lt;/p&gt;
&lt;p style=&quot;text-align: center; font-style: italic;&quot;&gt;or&lt;/p&gt;
&lt;p style=&quot;text-align: center;&quot;&gt;take a screen shot of your design and upload under the &amp;#39;submit a solution&amp;#39; tab &lt;a href=&quot;http://nrich.maths.org/public/submitsolution.php?time=1294658752&amp;amp;obj_id=7445&amp;amp;part=solution&quot;&gt;here&lt;/a&gt;&lt;/p&gt;
&lt;br&gt;&lt;/br&gt;
&lt;p&gt;&lt;span style=&quot;font-weight: bold;&quot;&gt;Challenge 1.&lt;/span&gt; Write instructions for: &lt;/p&gt;
    an equilateral triangle&lt;br&gt;&lt;/br&gt;
    a regular hexagon&lt;br&gt;&lt;/br&gt;
    a dodecagon&lt;br&gt;&lt;/br&gt;
    a circle.&lt;br&gt;&lt;/br&gt;
 &lt;br&gt;&lt;/br&gt;
&lt;span style=&quot;font-weight: bold;&quot;&gt;Challenge 2.&lt;/span&gt; Design a pattern which uses:&lt;br&gt;&lt;/br&gt;
   &lt;br&gt;&lt;/br&gt;
    five squares&lt;br&gt;&lt;/br&gt;
    six hexagons&lt;br&gt;&lt;/br&gt;
    three dodecagons&lt;br&gt;&lt;/br&gt;
    four circles.&lt;br&gt;&lt;/br&gt;
 &lt;br&gt;&lt;/br&gt;
&lt;span style=&quot;font-weight: bold;&quot;&gt;Challenge 3.&lt;/span&gt; Make a design based on spirals.&lt;br&gt;&lt;/br&gt;
 &lt;br&gt;&lt;/br&gt;
&lt;br&gt;&lt;/br&gt;
&lt;span style=&quot;font-weight: bold;&quot;&gt;Challenge 4.&lt;/span&gt; Can you find instructions that would result in this design?  Can you find a shorter set?&lt;br&gt;&lt;/br&gt;
 &lt;br&gt;&lt;/br&gt;
 &lt;mdo:image alt=&quot;TWILGO CHALLENGE FEB 2011&quot; height=&quot;587&quot; src=&quot;Screen%20shot%202011-01-10%20at%2011.56.59.png&quot; width=&quot;626&quot;&gt;&lt;/mdo:image&gt;&lt;br&gt;&lt;/br&gt;
&lt;br&gt;&lt;/br&gt;
&lt;span style=&quot;font-weight: bold;&quot;&gt;Challenge 5a.&lt;/span&gt;  Can you come up with a program that covers the Twilgo window with a tiling? &lt;span style=&quot;font-weight: bold;&quot;&gt;Challenge 5b.&lt;/span&gt; Can you think of a way of making an algorithm that would tile the whole plane (not just the Twilgo window) if left to run forever? This is hard and it may be impossible.&lt;br&gt;&lt;/br&gt;
Want more? There are more challenges &lt;a href=&quot;http://nrich.maths.org/7406&quot;&gt;here&lt;/a&gt;.&lt;br&gt;&lt;/br&gt;&lt;/mdoxml&gt;</indexXML>
  <solutionXML/>
  <noteXML/>
  <clueXML/>
  <canonXML/>
  <end_user_role>2</end_user_role>
  <difficulty>3</difficulty>
  <keystage1>1</keystage1>
  <keystage2>1</keystage2>
  <keystage3>1</keystage3>
  <keystage4>1</keystage4>
  <keystage4plus>1</keystage4plus>
  <title>Introducing NRICH TWILGO</title>
  <description>We're excited about this new program for drawing beautiful mathematical designs. Can you work out how we made our first few pictures and, even better, share your most elegant solutions with us?</description>
  <spec_group>Using, Applying and Reasoning about Mathematics
    <specifier>Making and testing hypotheses</specifier>
  </spec_group>
  <spec_group>Using, Applying and Reasoning about Mathematics
    <specifier>Working systematically</specifier>
  </spec_group>
  <spec_group>Using, Applying and Reasoning about Mathematics
    <specifier>Trial and improvement</specifier>
  </spec_group>
  <spec_group>Using, Applying and Reasoning about Mathematics
    <specifier>Visualising</specifier>
  </spec_group>
  <spec_group>2D Geometry, Shape and Space
    <specifier>Shape, space &amp; measures - generally</specifier>
  </spec_group>
</resource>