Build an Explore query using number view that will return an average of age filtered to events with action that matches purchase starting 1 month ago and ending now.
Once your query returns pay attention to the numeric value. Because we chose average of age instead of count of events our measure 1 is instructing the query to look for all unique values of age within the given time range (here we chose 1 month ago to now) and summing it then dividing it to returning the average value for measure 1.
Note: The numbers and result does not need to be an exact match as the data changes over time. The query construction is what is most important. See images below.
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