Excel count with 2 conditions

[janet]

I'm sure this is an easy one for you but I just can't get it to work
correctly. I have a spreadsheet that I want to count certain criteria.
Example:
A B C
Name Gender Score
Calvin M 3
William M 4
Jessica F 1
Sarah F 3
Bryan M 1
Anna F 3

I need to how many females scored a 3. What would you suggest I use for a
formula?

 

[Mike]

=SUMPRODUCT(--(B1:B6="F")*(C1:C6=3))

 

[wx4usa]

=SUMPRODUCT(--(B1:B6="F")*(C1:C6=3))

Just curious, what does the "--" in the formula do?