Below is a possible solution to the challenge Challenge 27 – Count the Number of Alphabets and Numerals and Other Characters.
The formula for counting number of alphabets
=SUMPRODUCT(LEN(A1)-LEN(SUBSTITUTE(UPPER(A1),CHAR(ROW(65:90)),"")))
The formula for counting number of numerals
=SUMPRODUCT(LEN(A1)-LEN(SUBSTITUTE(A1,ROW(1:10)-1,"")))
The formula for counting other characters
=LEN(SUBSTITUTE(A1," ",""))-C1-C2
Where C and C2 are number of alphabets and numerals.