import Foundation

func solution() {
    let input = readLine()!.split(separator: " ").map { Double($0)! }
    let n = input.first!
    let average = input[1...].reduce(0, +) / n
    let answer = Double(input[1...].filter { $0 > average }.count) / n * 100
    print(String(format: "%.3f", answer) + "%")
}

let c = Int(readLine()!)!
(1...c).forEach { _ in solution() }