Average multiple values from multiple sheets

Hi there,

I have this problem. I have 31 sheets regarding 31 days of the month. I need to add a certain value (on cell J45 in all sheets) and average it in the main sheet. Problem is i need to average day by day. after 10 days i get the 10 values and average them. Next day it does the same for 11 days and so on. Im thinking a condition cell in every sheet (like "state: on" for that sheet) and make a condition to add (or not) that "day". Is there an easy way around this?

Much appreciated

Hi there,

i had some trouble outside this situation that's the reason im replying just now. I figured out the last problem. now i have a new one. In main sheet i need to get a value from another sheet but only if that sheet is "active". In other words i still have 31 days and only 1 day active and i need to check all sheets to get the active day and get the value from a specific cell in that sheet.
Right now i use cell P34 from every sheet (31 sheets) and check if it is "ON" (actually has string ON in it if its active). i need to check all sheets to see wich one is ON and copy the value from another cell (P4) from that specific sheet to the main sheet. Is this possible? Or is there an easy way?

best regards