import java.lang.Math.sqrt

fun main(args:Array<String>?): Unit {
    val n = readLine()!!.trim().toInt()
    val ratio = DoubleArray(n){readLine()!!.trim().toDouble()}
    println(
            solve(ratio)
    )
}
fun solve(ratio: DoubleArray): Double {
    val sorted = ratio.sorted()
    val minProb = 0.0001
    val sumProb = 0.03
    val sumSqrt = DoubleArray(sorted.size + 1){i -> if (i in sorted.indices) sqrt(sorted[i]) else 0.0}
    var min = Double.MAX_VALUE
    for (i in sumSqrt.lastIndex downTo 1) sumSqrt[i - 1] += sumSqrt[i]
    for (useMinProb in sorted.indices) {
        val restProb = sumProb - minProb * useMinProb
        val sumSqrtFrom = sumSqrt[useMinProb] / restProb
        if ((useMinProb until sorted.size).all{sqrt(sorted[it]) / sumSqrtFrom >= minProb}) {
            val estimated = (0 until useMinProb).map { sorted[it] / minProb }.sum() + (useMinProb until sorted.size).map { sorted[it] * sumSqrtFrom / sqrt(sorted[it])}.sum()
            if (min > estimated){
                min = estimated
            }
        }
    }
    return min * 300
}
