#include<bits/stdc++.h> using namespace std; int main(){ double s,n,g,s1,n1,g1,jg; cin>>s>>n>>g; s1=s*10.4; n1=n*15.6; g1=g*25.2; jg=s1+n1+g1; printf("%.1lf",jg); return 0; }