#include <cstdio>
#include <vector>
#include <algorithm>
#include <cstring>
#include <string>
#include <cctype>
#include <sstream>
#include <cmath>
#include <climits>
#include <set>
#include <iostream>
#include <map>
#include <functional>
#include <cstdlib>
#include <numeric>
#include <queue>
#include <complex>
#include <sstream>
#include <stack>

using namespace std;

#define reep(i,f,n) for(int i=f; i<int(n); ++i)
#define rep(i,n) reep(i,0,n)

typedef vector<int> vi;
typedef pair<int, int> pii;
typedef complex<double> Point;

int main()
{
	char line[128];
	stack<double> st;
	while(fgets(line, 128, stdin)){
		istringstream sin(line);
		char str[128];
		while(sin >> str){
			if((strlen(str) > 1 && str[0] == '-') || isdigit(str[0])){
				st.push(atof(str));
			}else{
				double b = st.top();
				st.pop();
				double a = st.top();
				st.pop();
				if(str[0] == '+')
					st.push(a+b);
				else if(str[0] == '-')
					st.push(a-b);
				else if(str[0] == '*')
					st.push(a*b);
				else if(str[0] == '/')
					st.push(a/b);
			}
		}
		printf("%lf\n", st.top());
	}
	return 0;
}