Yes RSVP responses are 200 x 83% = <<200*83*.01=166>>166 guests.
No RSVP responses are 200 x 9% = <<200*9*.01=18>>18 guests.
Guests who responded are 166 + 18 = <<166+18=184>>184.
Guests who did not respond at all are 200 - 184 = <<200-184=16>>16.
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