#DIV/0! Error Fix

I am creating a "Summary" sheet using numbers from a separate "Detailed" sheet in the same workbook. Column B is the person's name and column G is the number of days. On the "Summary" sheet I want to calculate the average number of days for each name in column B using the formula below. Unfortunately, when the number of days is zero I get a #DIV/0! error on my "Summary" sheet and I would like to just make it zero.


=AVERAGEIF(Detailed!$B$5:$B$42, "JOE SMITH", Detailed!$G$5:$G$42)

The second issue I have is trying to average the averages on the "Summary" sheet while ignoring the #DIV/0! error.

I tried looking up how to use the IFERROR function with the above formula, but I received an error notice saying too many arguments.

Try:

=IFERROR(AVERAGEIF(Detailed!$B$5:$B$42, "JOE SMITH", Detailed!$G$5:$G$42),0)