#include <bits/stdc++.h>

using namespace std;

int main() {
    int juli, time;
    float money = 6.0;
    cin >> juli >> time;
    if (juli > 2 && juli <= 10) money += (juli - 2) * 1.8;
    if (juli > 10) money += (10 - 2) * 1.8 + (juli - 10) * 1.8 * .15;
    money += time / 3;

    cout << money << endl;
    return 0;
}