Ode to faulty maths exam maker(s)

Oh please God(s) show me *mercy*

Resolve test controversy

Don’t fault my suggestion

Result is in question

Resign please try reversi

Alan Grace

23 November 2017

This year the New Zealand NCEA Level 1 Maths exam sat this week by 28,000 (39,000?)students was problematic.

I have not seen the exam paper.

Have you tried the kite question?

Here’s another problem from the exam:

Today or tomorrow I will put a solution at the bottom of this page.

In the meantime, please email me your answer(s).

For a start let’s forget about the seat. The shape is a catenary, not a parabola.

The curve a hanging flexible wire or chain assumes when supported at its ends and acted upon by a uniform gravitational force is a catenary. The word catenary is derived from the Latin word for “chain.” In 1669, Jungius disproved Galileo’s claim that the curve of a chain hanging under gravity would be a parabola!

Now close to 350 years later, some maths teachers still may think it’s a parabola.

Let’s assume the shape is a parabola.

The swing seat is about 1.2m above the ground so kids could not use it easily.

The seat presumably is almost two metres long between the ropes.

Since a person’s arms’ span is close to his/her height only an adult could use the swing.

Also we need three points to define a parabola and we only have two in the diagram 🙁

However, looking at a video it seems the equation is probably modelled by

See:

http://www.newshub.co.nz/home/new-zealand/2017/11/maths-teachers-call-level-one-exam-a-disaster.html

http://www.newstalkzb.co.nz/on-air/larry-williams-drive/audio/jake-wills/

https://www.odt.co.nz/news/national/students-tears-over-maths-exam

This question reminds me of the diagram below.

When I originally saw a version of the diagram below (maybe over 40 years ago) it was entitled ‘Communication is the Key’.

Daily prompt: Mercy