Average If with multiple conditions
 

I have 5 columns of data and need a a formula that will allow me to calculate
the following:

Average the values of column E for all instances where column A = "P1" and
column B = "Red" and Column D = "20". I.e. the average will only be
calculated for the lines in column E where the above conditions have been met
in the other columns, as mentioned.

Average If with multiple conditions
 

Array formula (validate with Ctrl+Shift+Enter) :
=AVERAGE(IF((A1:A10="p1")*(B1:B10="red")*(D1:D10=2 0)=1,E1:E10))
HTH
Daniel

I have 5 columns of data and need a a formula that will allow me to calculate
the following:

Average the values of column E for all instances where column A = "P1" and
column B = "Red" and Column D = "20". I.e. the average will only be
calculated for the lines in column E where the above conditions have been met
in the other columns, as mentioned.