Does anyone know how they mark the 11+ papers?

Is it right that they average the marks out, say for instance the maths paper is worth 40 marks and the average mark for the 5000 or so kids is 25/40 that will equate to 100 points, so if a child gets say 30/40 on the maths paper they will get 110 points (this is just a guess as i haven't a clue how they work it) and if a child gets 20/40 on the maths they will get 90 points, and so on!

This is done for all 3 papers. so the average score would be 300 points??? Does anyone know what a child needs to get to gain a place in a grammar school ( i know they all vary)

Not sure if this is at all correct, but just what i have heard, it may all be completely wrong, any information would be well appreciated.

Hope everyone is well and not getting too stressed with the old christmas shopping

Joanne