ALL_PEOPLE       = 1000000
MAX_MAFIA_PEOPLE = 10000
N = gets.chomp.to_i

mafia_people  = ALL_PEOPLE / MAX_MAFIA_PEOPLE * N
common_people = ALL_PEOPLE - mafia_people
puts (common_people * 0.01 / (mafia_people * 0.99 + common_people * 0.01) * 100).to_f