I have a IF statement that is not working please help.

=if(AF3<=660,"Yes",if(AE3=50%,"Yes","No"). When I input 49% in AE3
it says Yes, when I need it to say No. It is counting AF3 as a 0,
when it is blank. I would also like to have the cell blank when both
AF3 and AE3 are blank.


Please help