Help on correct use of If statement within formula

[cpyates]

Hi I'm pretty new at using excell for more than anything really really simple but I have to put together a spreadsheet in work and I am stuck on what is probably really simple so any help will be really appreciated, I will try to explain it:

I want to display in a cell a sum but only if in the same row there is a value entered that I need. So for example in cell N17 I want to add Numbers from column K lets say K7 but only if in the same row in Column N7 has Y in it. Does that makes sense in my head its something like if(N7=Ythen+K7)

Please help

Thanks