object Main extends App {
  val sc = new java.util.Scanner(System.in)
  val a, b, t = sc.nextInt
//  val xss = List.fill(rows, cols)(sc.nextInt)

  val ans = Range(1, 20).map(i => (i * a, i * b)).foldLeft(0)((acc, v) => if (t + 0.5 < v._1) acc else v._2)
  println(ans)
}