CALCULATING TOTALS. I'm sure in the past I have been able to do this but seem to be having a senior moment and not getting any results so any help would be appreciated.

I simply want to add up a sequence of records and then divide them by another total from the same sequence. So I have two fields- AMOUNT and NUMBER and I want a total for each then I want to divide the total of AMOUNT by the total of NUMBER to get an average. I have used

AMOUNT : SUM;

NUMBER : SUM.

and that produces the totals okay , say AMOUNT= 25, NUMBER = 10 but what I also want is

(AMOUNT : SUM)/(NUMBER : SUM) to give me 25/10= 2.5.

Is there any way to achieveit- sure there must be!