I only know 5 :/
I think it would depend on who you talk to…some may say if you can play a song from start to finish than you can play a guitar, doesn’t have to be a complex song either. In the end though its all about you, if your comfortable saying to a possible girl/boy friend that you can play the guitar and she says play me something and you don’t feel like a fool afterwards than its safe to say you can play. Unless of course your a fool all the time 
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