//p1542
#include <bits/stdc++.h>
using namespace std;
const int N = 2 * 10e5;

struct node {
	long double x, y, s;
} a[N];
int n;

int cjc(long double x) {
	long double t = 0;
	for (int i = 1; i <= n; i++) {
		long double dis = a[i].s;
		t += dis / x;
		if (t > a[i].y)
			return 0;
		else {
			t = max(t, a[i].x);
		}
	}
	return 1;
}

int main() {
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> a[i].x >> a[i].y >> a[i].s;
	}
	long double l = 0, r = 10e7;
	long double ans = 0;
	while (r - l >= 0.00001) {
		long long mid = (l + r) / 2;
		if (cjc(mid)) {
			r = mid - 1;
			ans = mid;
		} else {
			l = mid + 1;
		}
	}
	cout << fixed << setprecision(2) << ans << endl;
	return 0;
}