/**
 * Easy, once you understand the numbers from example. I had to read the problems multiple times before I
 * how the examples make sense.
 * Calculate the time the rest of the process takes and use this to calculate the time of the new program takes.
 */
fun main() {
  val (before, after) = readln().split(" ").take(2).map { it.toDouble() }
  val restTime = 100 - before
  val newTotalTime = restTime / (100 - after)
  println((before) / (newTotalTime * after))
}