use std::io;

fn main() {
    let mut input = String::new();
    io::stdin().read_line(&mut input)
        .expect("Read error");
    let words: Vec<f64> = input.split_whitespace()
        .map(|w| w.parse().unwrap())
        .collect();

    println!("{}", solve(words[0], words[1], words[2]));
}

fn solve(n: f64, g: f64, v: f64) -> f64 {
    let n = n as u64 / 5;
    let n2 = n as f64;

    g  * n2 / v
}

#[test]
fn it_works() {
    assert_eq!(1000.0, solve(100., 500.0, 10.0));
    assert_eq!(335030261.51740766171,
               solve(187456612., 84877661., 9498174.));
}