calculating avg for field short time

[elisnery]

I'm trying to add a calculated member (measure) to give me the avg of time wait.
I added a measure with sum as aggregate formula. Add same measure again with count as aggeregate formula.
Then use a calculated measure with sum/count to get the average, but when I divide the field time by total, show a wrong value.
Calculated measure is formated with short time.
Where is the error?

Best Regards
Elis