#include<bits/stdc++.h>
using namespace std;
int main()
{
int i,n,c;
double m,a,b,sum,sum1,p;
cin>>n;
for(i=1;i<=n;i++)
{
sum=0,sum1=0,p=0,c=0;
cin>>m;
while(m--)
{
cin>>a>>b;
if(a>=80)
{
p=4*b;
}
else if(a>=75)
{
p=3.75*b;
}
else if(a>=70)
{
p=3.50*b;
}
else if(a>=65)
{
p=3.25*b;
}
else if(a>=60)
{
p=3*b;
}
else if(a>=55)
{
p=2.75*b;
}
else if(a>=50)
{
p=2.50*b;
}
else if(a>=45)
{
p=2.25*b;
}
else if(a>=40)
{
p=2*b;
}
sum=sum+b;
sum1=sum1+p;
if(a<40)
{
c++;
}
}
if(c>0)
{
cout<<"Case "<<i<<": Sorry, you have failed in "<<c<<" courses!"<<endl;
}
else
{
cout<<fixed<<setprecision(2)<<"Case "<<i<<": "<<sum1/sum<<endl;
}
}
}
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