#include <iostream>
using namespace std;
double num[100][2] = {
    {180.90, 88}, {10.25, 65}, {56.14, 90}, {104.65, 90}, {100.30, 88}, {297.15, 50}, {26.75, 65}, {130.62, 50}, {240.28, 58}, {270.62, 80}, {115.87, 88}, {247.34, 95}, {73.21, 90}, {101.00, 50}, {79.54, 50}, {278.44, 70}, {199.26, 50}, {12.97, 90}, {166.30, 78}, {125.50, 58}, {84.98, 90}, {113.35, 68}, {166.57, 50}, {42.56, 90}, {81.90, 95}, {131.78, 80}, {255.89, 78}, {109.17, 90}, {146.69, 68}, {139.33, 65}, {141.16, 78}, {154.74, 80}, {59.42, 80}, {85.44, 68}, {293.70, 88}, {261.79, 65}, {11.30, 88}, {268.27, 58}, {128.29, 88}, {251.03, 80}, {208.39, 75}, {128.88, 75}, {62.06, 90}, {225.87, 75}, {12.89, 75}, {34.28, 75}, {62.16, 58}, {129.12, 50}, {218.37, 50}, {289.69, 80}};
int main()
{
    double ans = 0.0;
    for (int i = 0; i < 50; ++i)
        ans += num[i][0] * num[i][1] / 100;
    cout << ans << endl;
    return 0;
}