AS a regular user of the A1(M) during the last few years of extensive roadworks in North Yorkshire, I’m not surprised that 15,000 drivers have received fines after being caught out by the 50mph average speed cameras (Echo, Sept 16).

It is obvious that those zooming along in the outside lane then slowing down for the cameras do not understand the simple concept of average speed cameras.

Clocking your time between two fixed points, then calculating your average speed between those points, is a very basic piece of physics.

G Carr, Aycliffe Village