#include <iostream>
#include <fstream>
#include <sstream>
#include <iomanip>
#include <complex>
#include <string>
#include <vector>
#include <list>
#include <deque>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <bitset>
#include <functional>
#include <utility>
#include <algorithm>
#include <numeric>
#include <typeinfo>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <climits>
#include <ctime>

using namespace std;

#define dump(n) cout<<"# "<<#n<<"="<<(n)<<endl
#define debug(n) cout<<__FILE__<<","<<__LINE__<<": #"<<#n<<"="<<(n)<<endl
#define repi(i,a,b) for(int i=int(a);i<int(b);i++)
#define rep(i,n) repi(i,0,n)
#define iter(c) __typeof((c).begin())
#define foreach(i,c) for(iter(c) i=(c).begin();i!=(c).end();i++)
#define allof(c) (c).begin(),(c).end()
#define mp make_pair

typedef unsigned int uint;
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<string> vs;
typedef pair<int,int> pii;

double solve(vs& ss)
{
	stack<double> st;
	rep(i,ss.size()){
		if(isdigit(ss[i][0]))
			st.push(atof(ss[i].c_str()));
		else{
			double a,b;
			b=st.top();st.pop();
			a=st.top();st.pop();
			
			switch(ss[i][0]){
				case '+':
					st.push(a+b);
					break;
				case '-':
					st.push(a-b);
					break;
				case '*':
					st.push(a*b);
					break;
				case '/':
					st.push(a/b);
					break;
			}
		}
	}
	return st.top();
}

int main()
{
	for(string s;getline(cin,s);){
		istringstream iss(s);
		vs ss;
		for(string s;iss>>s;ss.push_back(s))
			;
		printf("%f\n",solve(ss));
	}
	
	return 0;
}