#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef long double ld;
typedef tuple<int, int> duo;

#define TT template<typename T>
#define ET(T) typename T::value_type
TT inline T sq(T x){return x*x;}
TT inline T In(){T x;cin>>x;return x;}
TT inline int ubnd(T&v,ET(T) x){return upper_bound(begin(v),end(v),x)-begin(v);}
TT inline int lbnd(T&v,ET(T) x){return lower_bound(begin(v),end(v),x)-begin(v);}
TT inline void sort(T&v){sort(begin(v),end(v));}
TT inline void revs(T&v){reverse(begin(v),end(v));}
TT inline void uniq(T&v){sort(v);v.erase(unique(begin(v),end(v)),end(v));}
TT inline void inpt(T&v,int n,function<ET(T)()>f=In<ET(T)>){for(v.reserve(n);n--;v.emplace_back(f()));}
TT inline void show(T&v,string d=" ",string e="\n"){int i=0;for(auto&x:v)i++&&(cout<<d),cout<<x;cout<<e;}
#undef TT
#undef ET

inline void fast_io(){ios::sync_with_stdio(0); cin.tie(0);}
inline int in(){int x;scanf("%d",&x);return x;}
inline string instr(){string x;cin>>x;return x;}
inline ll pow_mod(ll a, ll k, ll m){ll r=1;for(;k>0;a=a*a%m,k>>=1)if(k&1)r=r*a%m;return r;}
inline ll mod_inv(ll a, ll p){return pow_mod(a,p-2,p);}

const int dx[] = {0, 0, 1, -1, 1, 1, -1, -1};
const int dy[] = {1, -1, 0, 0, 1, -1, 1, -1};
const int Mod = 1000000000;

bool is_digit(const string& s){
  if (isdigit(s[0])) return true;
  return (s[0] == '+' || s[0] == '-') && isdigit(s[1]);
}

int main()
{
  string line;
  while (getline(cin, line)){
    stringstream ss(line);
    string e;
    stack<ld> st;
    while (ss >> e){
      if (is_digit(e)) st.push(stof(e));
      else {
        ld a, b;
        a = st.top();
        st.pop();
        b = st.top();
        st.pop();
        if (e == "+") st.push(b + a);
        if (e == "-") st.push(b - a);
        if (e == "*") st.push(b * a);
        if (e == "/") st.push(b / a);
      }
    }
    printf("%Lf\n", st.top());
  }
  return (0);
}

// priority_queue queue deque front top push pop map set stringstream max_element min_element insert count find get tie make_tuple