SUMPRODUCT(...)
Using sumproduct to validate for multiple criteria.
Used Functions
Category: Math and trigonometry
Returns the sum of the products of corresponding array components
Syntax
SUMPRODUCT(array1, [array2], [array3], ...)
Practice SUMPRODUCT Formula at Sheetzoom
SUMPRODUCT formula at Microsoft help
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This formula checks for the given criteria, then this process continues and we get an array of the TRUE and FALSE that multiplies with 1 to get the fina lresult.