#include <iostream>
#include <cstdio>
#include <cmath>
#include <algorithm>
using namespace std;

int main() {
    int n, d;
    double a, b;
    double maxtan = 0;
    cin >> n >> d;
    for (int i = 0; i < n; i++) {
        cin >> b >> a;
        double c = a / b;
        maxtan = max(maxtan, c);
    }
    printf("%.6lf\n", maxtan * d);
    return 0;
}

