Archive for the ‘Junior School’ Category

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Amazing Maths Clock

March 17, 2018

Albert Digital Mathematical clocks are fascinating.

You calculate the time using +, -, x and ÷ . Such fun and ideal for the math classroom.

Mathspig found the Albert Mathematical clock at the Horsham International Hotel (below).

More info on the Albert Digital Clock here.

You can set the level of difficulty. You get 1 minute to work out the answer and that’s long enough.

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Winter Olympics: Bad Math of Figure Skating Scores

February 22, 2018

According to the fab NBC video, Mathletes,  nine Figure Skating judges score competitors for the complexity of each element (eg. Triple axel or triple spin jump) and the quality of the performance producing a score out of ten.

Tessa Virtue and Scott Moir win GOLD at Pyeong Chang 2018

                                   Kailani Craine, Australia

figure skating score 9 judges nbclearn

This is a typical figure skating score card for one competitor.

The final score, however, is based  on the average for only 5 of these scores. Two are eliminated by random selection (Red Brackets). Then the top and bottom scores are removed and the remaining five scores averaged.

Screen grab NBC Mathletes

Screen grab NBC Mathletes

……………………………………………………

Now consider the IDENTICAL SCORE CARDS

of Skater A & B:

figure skating score A

Skater A:

Four scores are removed. Two by the random selector (in brackets) and then the top and bottom scores (with line drawn through them)

7.00 + 7.00 + 7.00 + 6.75 + 7.00

……………………………………..

=  34.75/ 5 = 6.95

figure skating score B

Skater B:

Four scores are removed. Two by the random selector (in brackets) and then the top and bottom scores (with line drawn through them). But this time the random selector eliminates two low scores.

The average:

7.00 + 7.25 + 7.00 + 7.00 + 7.00

……………………………………..

=  35.25/ 5 = 7.05

Same score cards but Skater B gets a higher average score than Skater A.

Skater A is, in fact, beaten by a random number selector!!!!

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Winter Olympics: Beaten by 0.001 seconds

February 14, 2018

 

In 2014 Winter Olympics Annette Gerristen (below) lost the Gold Medal in the 1000 m Women’s speed skate competition by 0.02 seconds.

Annette Gerritsen fromthe Netherlands

Annette Gerritsen fromthe Netherlands

What are the speed skating times for women?

Women’s Speed Skating Calulations:

Here are the speed calcs for Yara Van Kerkhof of the Netherlands in the 2018 Winter Olympics:

If Yara lost the Gold Medal by 0.02 secs (2 hundredths of a second) what would the distance be between the Gold and Silver place getters?

When 1st and 2nd place are separated by 0.02 seconds, they are travelling at almost the same speed. So the second place contestant is:

23.8 cm behind the Gold Medalist

The 2018 Olympic Gold Medalist in the 500m Women’s Speed Skating was Arianna Fontana.

Italy’s Arianna Fontana wins the 500 m Speed Skating 2018 Olympic Gold Medal in 42.569 seconds ahead of Yara van Kerkhof of the Netherlands and Kim Boutin of Canada. 

Men’s Speed Skating:

At longer distances the men’s speed skating speed is similar to the women’s speed above.

If you lose by  0.001 secs…………

Apollo Ono (below) competed in the 1500m men’s speed skating. He has won 8 Olympic Medals.

If a speed skater lost the Gold Medal by 0.001 seconds, the smallest measured time segment at the Olympics, they would be:

1.19 cm

behind the winner. That is less than the length of a small fingernail.

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Survival Maths: Close encounters with Sharks

January 12, 2018

Drone’s Eye View: AWESOME!!!!!

Australia takes it’s sharks very seriously. Shark detecting drones are being trialled on beaches in NSW as a part of the NSW Government’s $16 million Shark Management Strategy. 

The film JAWS has given sharks a bad rap. Here are the STATS:

Deaths by shark attack in the world:

Australia       About 2 a year

USA               1 every 2 years 

UK                  None EVER

CANADA          None EVER

More deaths occur due to falling off chairs in Australia. Quad bikes are deadly anywhere. 

Full Stats and references here.

Meanwhile,  you see a shark fin. You can swim BUT what distance do you need to be from the shark to make it to the beach.

You will find some interesting maths here.

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2a. If all the cars in the world were parked together what area would they cover? Metric Units

November 28, 2017

*For the year 2015 by Statista here.

Area by Country

Area by State USA
…………………

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2b. If all the cars in the world were parked together what area would they cover? USA UNITS

November 28, 2017

*For the year 2015 by Statista here.

Area by Country

Area by State USA

………………….

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3. Middle School Madness: BIG MATHS

May 25, 2017

Mathspig loves this ‘Street Art’ time lapse clip made by projective geometry students at the Technical University, Munich. 

SO … thought Mathspig … lets do it! Two days later Mathspig’s eyes nearly crossed trying to locate the Vanishing Point (below), which helps artists draw 3D images. It didn’t work due to the angle of elevation of the camera. 

SO .. rethink needed. (See project 1 & 2 below)

Maths Meets Street Art:

Project 1

Students can draw this ‘hole in the earth’ by Circle/Line Art School on paper fairly quickly. The aim here is to practice 3D street Art.

Maths Meets Street Art:

Project 2: The BIG ONE

Students can draw this ‘concrete hole’ by MiltonCor on paper using a ruler, set square and pencils. Then they have to scale it up to a size large enough for them to sit on the steps. The class can the ‘concrete hole’  in chalk in the school yard. Basic shading only is required, not the shading detail shown in this video.

Finally, students can take a photo of themselves sitting on the ‘steps’ with maths books beside them. 

Another MATHS SELFIE!!!!