. 36 people {a1, a2, …, a36} meet and shake hands in a circular fashion. In other words,
there are totally 36 handshakes involving the pairs, {a1, a2}, {a2, a3}, …, {a35, a36}, {a36,
a1}. Then size of the smallest set of people such that the rest have shaken hands with at least
one person in the set is
a)12 b)11 c)13 d)18

• 12 persons.
  a2,a5,a8.........a35
  
  as a2 shook hands with a1 and a3.
  a5 shook hands with a4 and a6.
  ..
  ..
  a35 shook hands with a34 and a36.
• 13 years agoHelpfull: Yes(3) No(0)
• 12(36/3)
  1-2-3
  4-5-6
  .
  .
  .
  
• 13 years agoHelpfull: Yes(0) No(1)