How to divide one measure by another

Question

Sample Dataset:

school  student marks
a       xyz      5
a       xyz      10
a       abc      15
b       cde      20
b       cde      25
a       cde      30

Goal: Find total marks, count of marks and average marks by student and school

Query: How can I create the 4th column when 2nd and 3rd columns are measures. Is it possible to perform a row level calculation?

student sum of marks    count of marks  average marks
xyz      15              2               7.5
abc      15              1               15
cde      75              3               25

school  sum of marks    count of marks  average marks
a       60              4               15
b       55              2               27.5

Answer 1

Yes it is possible,

Option 1:

Create a calculated field as "average marks":

SUM(marks)/COUNT(marks)
 

Option 2:

Right click the measure and select average from the options instead of sum or count.