Create measure that computes average over groups of rows

[bipolarminds]

I am given a table table1 with columns A, B, C and D. I would like to group rows that have same column entry in A, B and C. Then I would like to count the rows in every group, so that I can vizualize the average group size in the category defined by column C.

How can I achieve this?

[amitchandak]

@bipolarminds , No vary clear

you need like

AverageX(filter(allselected(Table), [C] = max(Table[C]) ) , Table[Value]))

or

calculate(AverageX(values(Table[C]) , calculate(Sum(Table[Value]))),filter(allselected(Table), [C] = max(Table[C]) ))