import java.util.Scanner

object Problem191 {

  def proc(c: Seq[Int]): Int = {
    val totalVote: Int = c.sum
    // totalVoteの方を10で割ると丸められて面倒
    c.count(_ * 10 <= totalVote) * 30
  }

  def main(args: Array[String]) {
    val sc = new Scanner(System.in)
    val n = sc.nextInt()
    val c = Seq.fill(n)(sc.nextInt())

    val result:Int = proc(c)
    println(result)
  }
}