In this case,we have to use
=SUMPRODUCT(1/COUNTIF(SELECT RANGE,CRITERIA))
Note:-
HERE,
Range and Criteria are same,hence Formula actually is
=SUMPRODUCT(1/COUNTIF(SELECT RANGE,SELECT RANGE))
EXAMPLE
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View AnswerFor Question 1: To Calculate how many subjects.
We can make a pivot table and count the subjects.
or
We can use countif and sumproduct formula
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