"Are you older than me?"
Translation:Benden büyük müsünüz?
"Are you older than me?" - Benden büyük müsünüz?
Polite/formal spoken Turkish & grammatically plural.
Benden büyük müsün? - "Are you older than me?"
Spoken to an individual or well known person & grammatically singular.
You have to use your personal judgement. I always use "müsün?" to an individual & "müsünüz?" to more than one individual. So far no one has taken offence.