import std.stdio, std.conv, std.math, std.string, std.range, std.array,
       std.algorithm;

void main() {
  auto buf = readln().strip().split().map!(to!ulong)().array();
  immutable N = buf[0];
  immutable G = buf[1];
  immutable V = buf[2];

  auto grk = N/5*G;
  write(grk/V);
  auto a = grk%V*10^^8;
  writeln(".", a/V, a%V*10^^6/V);
}