human
A company is hosting a seminar. So far, 30 attendees from company A have been registered; company B has twice the number of attendees of company A; company C has 10 more attendees than company A; company D has 5 fewer attendees than company C. If a total of 185 attendees have registered, how many attendees who registered are not from either company A, B, C or D?
assistant
How many attendees are from company B? ** There are 30 x 2 = <<30*2=60>>60 attendees from company B.
How many attendees are from company C? ** Company C has 30 + 10 = <<30+10=40>>40 attendees.
How many attendees are from company D? ** Company D has 40 - 5 = <<40-5=35>>35 registered attendees.
How many attendees are from the four companies? ** So, the total attendees from company A, B, C, and D is 30 + 60 + 40 + 35 = <<30+60+40+35=165>>165.
How many attendees are not from companies A, B, C, or D? ** Therefore there are 185 - 165 = <<185-165=20>>20 attendees that are not from companies A, B, C, or D.
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