Polygon Riddle 2

?

My first is in shape but not in space;

My second is in line and also in place;

My third is in point but not in line;

My fourth in operation but not in sign;

My fifth is in angle but not in degree;

My sixth is in glide but not symmetry;

My seventh in round but not in square;

My last is in patterns you see everywhere;

My whole is a polygon, regular not wide;

But what is the sum of the angles inside?

Hint: split the shape into triangles

A Mathematics Lesson Starter Of The Day

Topics: Starter | Riddles | Shape

• Transum,
•
• This form of a riddle or word puzzle used to be more popular than it is today. The structure of the riddle is that each line (the first seven lines in this case) gives a clue to a single letter of the answer. The last line (the eighth line in this case) then gives a clue to the complete answer.
You can work out from line one that the first letter of the answer occurs in the word ‘shape’ but it does not occur in the word ‘space'. By process of elimination you can see that the first letter of the answer must be H.
Work through the other lines of the riddle to determine what the other letter possibilities and then you are well on your way to solving the riddle.
• Hayley Roberts, Gloucestershire
•
• The last line of the riddle asks what is the total of the inside angles of the polygon and the answer states 900 degrees. I do not believe this to be correct as the total of the internal angles of any polygon only add up to 360 degrees.
• Tracey Roden, ICC
•
• I thought it was the EXTERNAL angles of a polygon which total 360! Think triangle - the internal angles add up to 180!!
• Doyle,
•
• The exterior angles sum to 360
and the interior angles depends on how many sides the shape has,
a heptagon has 7 sides and therefore it can be split into 5 triangles
a triangle has 180 degrees, so 180*5 = 900.
• Rob Irving, Higham
•
• Internal angles of any polygon follow the formula n-2 x 180 where n= the number of sides of the polygon so the reason that a triangle has 180 degrees is becan(which = 3) - 2 x 180 means 1 x 180.
Try the formula for a rectangle and you get 360 degrees.
And yes it's true for all polygons. External angles are different they add up to 360.

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Christmas Present Ideas

It is often very difficult choosing Christmas presents for family and friends but so here are some seasonal, mathematics-related gifts chosen and recommended by Transum Mathematics.

Equate board game

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How Not To Be Wrong

The maths we learn in school can seem like an abstract set of rules, laid down by the ancients and not to be questioned. In fact, Jordan Ellenberg shows us, maths touches on everything we do, and a little mathematical knowledge reveals the hidden structures that lie beneath the world's messy and chaotic surface. In How Not to be Wrong, Ellenberg explores the mathematician's method of analyzing life, from the everyday to the cosmic, showing us which numbers to defend, which ones to ignore, and when to change the equation entirely. Along the way, he explains calculus in a single page, describes Gödel's theorem using only one-syllable words, and reveals how early you actually need to get to the airport.

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Graphic Display Calculator

This handheld device and companion software are designed to generate opportunities for classroom exploration and to promote greater understanding of core concepts in the mathematics and science classroom. TI-Nspire technology has been developed through sound classroom research which shows that "linked multiple representation are crucial in development of conceptual understanding and it is feasible only through use of a technology such as TI-Nspire, which provides simultaneous, dynamically linked representations of graphs, equations, data, and verbal explanations, such that a change in one representation is immediately reflected in the others.

For the young people in your life it is a great investment. Bought as a Christmas present but useful for many years to come as the young person turns into an A-level candidate then works their way through university. more...

The analytics show that more and more people are accessing Transum Mathematics via an iPad as it is so portable and responsive. The iPad has so many other uses in addition to solving Transum's puzzles and challenges and it would make an excellent Christmas gift for anyone.

You have to hold iPad Air to believe it. It’s just 7.5 millimeters thin and weighs just one pound. The stunning Retina display sits inside thinner bezels, so all you see is your content. And an incredible amount of power lies inside the sleek enclosure. So you can do so much more. With so much less. more...

Aristotle's Number Puzzle

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Keep the Maths in Christmaths with this reasonably priced stocking filler. more...

The Story Of Maths [DVD]

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Marcus du Sautoy's wonderful programmes make a perfect Christmas gift more...

Click the images above to see all the details of these gift ideas and to buy them online.

 Teacher, do your students have access to computers?Do they have iPads or Laptops in Lessons? Whether your students each have a TabletPC, a Surface or a Mac, this activity lends itself to eLearning (Engaged Learning).

Transum.org/go/?Start=July28

Here is the URL which will take them to a related student activity.

Transum.org/go/?to=Polyang

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