#include <bits/stdc++.h>
using namespace std;
using namespace chrono;
#if __has_include(<atcoder/all>)
#include <atcoder/all>
using namespace atcoder;
#endif

int main()
{
    int64_t T;
    cin >> T;

    for (int64_t t = 0; t < T; t++)
    {
        long double p;
        int64_t k;
        cin >> p >> k;

        map<int64_t, long double> mp;

        auto f = [&](auto &&g, int64_t x) -> long double
        {
            if (mp.find(x) != mp.end())
            {
                return mp[x];
            }

            if (k <= x)
            {
                return mp[x] = 0;
            }

            long double ret = 1 + (1 - p) * g(g, x + 1);

            return mp[x] = ret;
        };

        cout << fixed << setprecision(20) << f(f, 0) << endl;
    }

    return 0;
}