Archive for the ‘Area’ Category


Maths Mystery Box 4: FUNNY THAT

March 3, 2015

Maths Mystery BOX 4

1 BArt Simpson Death Wish

 Quadratic Equation  joke MathspigGraffiti pic found @ imfunny blog.

Maths is full-on full of humour.

Can you die laughing, sir?

Try these weird death stats.

Or, how about some maths jokes?

Or, how about a Maths Scavenger hunt.

Funny that!

Many maths teachers come up with great ideas so middle school students have fun with maths. Here are a few:

Human Graphs, Charts and Diagrams

Ellies Active Maths

2 line-graph   Ellie's graphs activemaths


How about a human bar graph?

3 human bar graph stenhouse  pinterest

Or a student linear graph?

4 human graph  bigpic     thecolab

Find more @ the colab


Or explore geometry through, well, dance?

6 Geometry dance

These students are showing supplementary angles

7 Geometry dance

These students are acting out the concept of complementary angles.

Tricia Appel; Middle School Math

Or, how about the geometry of yoga?

Mathspig groaning pig pose

Can you get your leg or knee to make a perfect right angle?

Or how about a Venn Diagram using Hola Hoops?

9 student venn diag

More info at Howard’s Happy Campers

Or you can measure length using bodies.

How many Smoots long is your football field?

Another Smoot, Oliver Smoot, is used to measure the length of the bridge in 1962.

Oliver Smoot is used as a unit of measure in 1962. 

Or try measuring the area of your school hallway in bodies!!!!

10 y4 rainbow school bradford uk

More info @ Rainbow school, Bradford, UK.


3. How maths rules ski jumping

January 23, 2014

While air resistance has little impact on aerial skiers (above) it is a significant factor used by ski jumpers to increase their jump distance.

The significant maths for ski jumpers is therefore X-section area.

Here is the jump at Sochi. Just imagine going down that at top speed!!!

Sochi Ski Jump 2014 by blogger Melbourneer

Sochi Ski Jump 2014 by blogger Melbourneer

Ski jumpers increase their speed going down the ramp by reducing their X-section area:

Lindsey Van, USA, practicing in a wind tunnel

Lindsey Van, USA, practicing in a wind tunnel

Once they leave the ramp, ski jumpers try to increase their X-section area like Ski Divers to slow their vertical fall. But they have to land safely so they keep their skis at a minimum  angle.

Abby Hughes going down jump:

Abby Hughes, USA, practicing in a wind tunnel.

Abby Hughes, USA, practicing in a wind tunnel.

Abby Hughes, USA, in the air

Abby Hughes, USA, in the air

Here are the X-section areas for Abby Hughes*:

Abby Hughes X-section

Here is the formula for Air Resistance of Drag:

D = ½CApv2

Where C is the drag coefficient or constant, which depends on the shape and spin of an object. It is found by testing the object in a wind tunnel.

A is the X-section Area,

p is the density of the air and

v the velocity of the object.

More here.

As Abby Hughes has tripled here X-section area in the air she will

have tripled the vertical drag during her jump. This will slow here decent.

*Mathspig calculated the X-section area by the old fashioned method of counting squares and rounding off the final count. Mathspig sized the two pics of Abby Huges so that her head was the same size in both pictures.


1. Design a Monster Duck

November 7, 2013

Dutch conceptual artist Florentijn Hofman has entertained millions around the world with his Monster Rubber Ducks.

pic 1 duck Rubber-Duck-Florentijin-Hofman-21-537x357

Different sized ducks have appeared in Amsterdam, Lommel (Belgium), Osaka, Sydney, Sao Paulo, Hong Kong and Pittsburgh.

pic 2 duck

Each duck is constructed using 3D and Computer computer generated models.

More here. 

pic 3 Hofman duck construction

pic 4 rubber duck beak

The Duck that appeared in Darling Harbour, Sydney in 2013 measured approx 15 m x 15 m.

It was FIVE STORIES high.

The largest duck, which appeared in Saint Nazaire, France measured approx 25 m high or 82 ft and weighed almost 600kg or 1300 lbs.

This mega duck is over 8 stories high!!!!!

BUT how does an artist stop the wind picking up an 8 story duck and dumping it on your head?

He – Florentijn is a he – does his maths.

Here is a simple wind load formula for stormy conditions.

F = Kv2A

F  = Wind Force (Newton)

K = Coefficient of Exposure = 0.5 (Engineers use standard tables for K)

v = Wind velocity = 72 kph = 20 m/sec

A = area of X-section exposed to the wind

Pic 5

Now, we’re going to be tricky. A 1 kg weight (eg. a litre of milk) exerts a force of 9.8 N or 1 kgf = 9.8 N on your hand. If we divide the above formulae by 10 we end up with a unit we know …. kgf.

F = Kv2A/10   kgf

pic 7


If the wind force is 9,560 kgf in a storm it can easily pick up a 600kg duck. In fact, if you do the calcs, it is only in a normal wind ( 20 kph or 5 m/sec) that the duck would stay put (F = 597 kgf).


If that duck is not tethered to a building or pontoon it could take off and it could easily take out a school!!!!!

pic 8


9 Build Your Own Battleship

April 9, 2013

Maths-is-Awesome Activity

Build Your Own Battleship

Skills: geometry, measuring, angles, construction and engineering

Years: Middle School

You will find your inspiration here:


Different maths classes build their own cardboard boats. Call for volunteers  and then stage a race in a local pool.

Heaps of fun.

Good PR for maths. And some schools do it already.


10 DYI Construction Set

April 8, 2013

Maths is Awesome Activity

DYI Construction Set

Skills: Geometry, measurement, symmetry, area, angles.

Year Level: Year 7

You will find more info here.

95 Happy Hooligans Construction Set

This idea is gobsmacking. We live in a consumer world so the thought of making your own construction set is foreign to us.

Building your own cardboard construction set involves:

* Lots of maths

and if

* Every pupil made 20 construction pieces now you can make something huge for a maths display. eg. giant parabola, π, √2


think really BIG.

95.4 zimoun_zweifel_200_motors_2000_cardboard_elements_01_800x450px

More info here at Building Blogspot.



12. Maths Warriors

April 8, 2013

The Maths-is-Awesome Activity:

Maths Warriors

Skills:Geometry, measurement, cylinders, area, symmetry and creativity.  

Year Level: Year 4 – whatever

93 box wars 4

Ask students to build their own cardboard armour and helmet. Give prizes in the category of Scariest, most Mathematically-Complex, Star Wars Potential, Most Historical, Most Creative and any other category that crops up. You can source cardboard from your nearest Self-Storage Warehouse.

93 box wars 5

Mathspig was at Womadelaide Music Festival 2013 and saw the Box Wars at work. The Box Wars guys, Joss, Josh and Hoss, started in Melbourne and now travel to Music Festivals around Australia. Boxwars builds sculptures, armour, props and sets and airplanes , tanks, cannons and the rest.

They stage battles of destruction … but destruction isn’t always the outcome.

93 box wars 3

If you want to interest kids especially boys 8 – 12 years of age in maths, get them building armour.

Mathspig saw dozens of them at WOMAD and they so loved their armour they wouldn’t take it off in 39Cº.

93 Fantasy armor pattern


Sometimes it is just lots and lots of fun. Here is a recently staged BOX WARS in Canberra. You only need watch a few minutes of the video to get the idea.

Box Wars Canberra




12 minute Maths Guru

July 4, 2011

Meet Salman Khan. He has put free maths on-line.

This article on Salman appeared in The Sunday Times, UK, 12 JUN 2011.

Salman, 28, started putting tutes online for his 12-year-old niece, Nadia, and things grew. So far the Kahn Academy’s claim to fame are:

* Over 2,400 videos including hundreds and hundreds of 12-minute maths tutes

* Over 63,000,000 lessons delivered.

* Bill Gates kids use the site.

* A staff of 1 with funding from The Bill and Melinda Gates Foundation.

* Tutes on Biology, Chemistry and Physics too.

You can look up the maths tutes by topic @ The Khan Academy.

Or search topics on Youtube eg. Introduction to Conics Khan

Why Does Mathspig like The Kahn Academy? Because it’s:

1. Free.

2. Quick

3. Clear

4. Low-key







Salman gives digital chalk-and-talk tutes like a teacher. He hand draws the equations and graphs. He uses a calculator from time to time, but he tends not to use whizz bang spreadsheet graphs or perfectly presented textbook equations. It’s a bit wobbly and it’s all coming from Salman’s head.

And students like this approach. It makes maths look do-able.

Go, Salman.

Mathspig thinks you are just GORGEOUS!!!!!!!!!

 Australia’s Year 7 – 12 Maths Curriculum is already on-line and free, funded by McDonald’s. See What are maths teachers for, sir?

The tutes on Maths Online are produced by Aussie Maths teachers and they are very good. Mathspig, of course, imagined the quadratic function tutes might look something like this: