#include<bits/stdc++.h>
using ll  = long long;
#define int ll
#define rep(i,n) for(int i=0;i<n;i++)
#define loop(i,s,n) for(int i=s;i<n;i++)
#define erep(e,v) for(auto && e :v)
#define all(in) in.begin(), in.end()
#define MP make_pair
#define INF (sizeof(int) == 4 ? (int)1e9:(int)1e18)
#define EPS 0.0000000001
using namespace std;
template<class T, class S> void cmin(T &a, const S &b) { if (a > b)a = b; }
template<class T, class S> void cmax(T &a, const S &b) { if (a < b)a = b; }
template<typename Head, typename Value> auto vectors(const Head &head, const Value &v) { return vector<Value>(head, v); }
template<typename Head, typename... Tail> auto vectors(Head x, Tail... tail) { auto inner = vectors(tail...); return vector<decltype(inner)>(x, inner); }
template<class T> void join(T a){for(auto itr :a){if(itr != *a.begin())cout << " "; cout << itr;} }
using ld  = long double;
using pii = pair<int,int>;
using piii = pair<int,pii>;
int W,H;
int dx[]={0,0,1,-1}, dy[]={1,-1,0,0};
bool valid(int x,int y){return (0<=x&&x<W)&&(0<=y&&y<H);}
signed main(){
    string s;
    while(getline(cin,s)){
        stack<double>st;
        string temp = "";
        s.push_back(' ');
        rep(i,s.size()){
            if(s[i] == ' '){
                if('0'<=temp.back() and temp.back()<='9'){
                    st.push(stod(temp));
                }else{
                    char op = temp.back();
                    auto a = st.top();st.pop();
                    auto b = st.top();st.pop();
                    double res = 0;
                    if(op == '*') res = a*b;
                    if(op == '+') res = a+b;
                    if(op == '-') res = b-a;
                    if(op == '/') res = b/a;
                    st.push(res);
                }
                temp.clear();
            } else {
                temp.push_back(s[i]);
            }
        }
        cout << fixed << setprecision(10) << st.top() << endl;
    }
}



