#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n;
    cin>>n;
    for(int i=0;i<n;i++)
    {
        double p,r;
        cin>>p>>r;
        double profit=p*r/100;
        cout<<fixed<<setpricision(2)<<profit<<endl;
    }
    return 0;
}