SUM(...)
Calculate Friday's between two dates
Used Functions
Category: Math and trigonometry
Adds its arguments
Syntax
SUM(number1,[number2],...)
Practice SUM Formula at Sheetzoom
SUM formula at Microsoft helpCategory: Text
Formats a number and converts it to text
Syntax
TEXT(Value you want to format, “Format you want to apply to that value”)
Category: Lookup and reference
Returns the row number of a reference
Syntax
ROW([reference])
Category: Lookup and reference
Returns a reference indicated by a text value
Syntax
INDIRECT(ref_text, [a1])
0
The formula takes the difference of two dates and adds it up in the start date to get all the dates in the range. Then it uses TEXT() function to format it as first three letters of the day and then perform match and sum the count.