What kind of a madman . . . .

[mollykins]

. . . . . . tries to explain the proof (including steps in the formulae) of how the shortcut for standard deviation is derived from the long winded way? And during 5th lesson on a Friday?

Something like that has never gone in one ear and out the other in that way.

[mrs_overall]

Shocking!

[ljdksa]

a Maths Teacher

[factor-fiction]

Oh, sounds like the sort of thing I'd do, mollykins. Maybe Friday afternoons in 6th form should be kept free for 'calculated colouring'.

[ttfn]

Did he use a thread from AB to explain it all ?

[sherrardk]

Maybe you can suggest that you make a poster next time you have a lesson on a Friday afternoon?

[mollykins]

We did standard deviation and rmsd or whatever it is on tuesday and then at the start of the lesson this afternoon he told us that there's an easier way but he didn't want the formula to come out of nowhere, so he thought he start with the long formula then cancel it down then multiply by n, then divide by it, for a reason which I still don't understand, then he ended up with this slightly simpler equation, after using a whole side of whiteboard to write out all the steps!

[A1Mikey]

How 'mean' of him....

[mollykins]

Indeed :P