Question about M1 moments for Edexcel

Hey guys. Ive realised that in some moments questions, you are told to add a particle to a system is equilibrium. They dont tell you the distance, but you are expected to put it in the right place on your diagram. Sometimes it is obvious whereabouts to place it on the diagram, other times its not. Ive lost many marks for having a wrong diagram and so i get the wrong answer. How are you supposed to know where to place the particle on to the diagram? Thanks in advance guy

One of the many mysteries of the world.

Lol no actually you just need to use a bit of logic and that's ol brain but it honestly really doesn't matter where you put it on the diagram though, if you put it on the right side then you'll get a positive answer
on the wrong side you get a negative answer, just remember though that that means the distance is on the other side from the point at which you take moments

so im guessing that the fact I've got questions like this wrong is due to a math error, not where the particle is on the diagram?

most likely, your calculations with an error rather than where you put the particle on the diagram