hdu5984
/**/
#include <cstdio>
#include <cstring>
#include <cmath>
#include <cctype>
#include <iostream>
#include <algorithm>
#include <map>
#include <set>
#include <vector>
#include <string>
#include <stack>
#include <queue>
typedef long long LL;
using namespace std;
int n;
double a, b;
int main()
{
//freopen("in.txt", "r", stdin);
//freopen("out.txt", "w", stdout);
scanf("%d", &n);
for (int i = 1; i <= n; i++){
scanf("%lf %lf", &a, &b);
if(a <= b){
printf("0.000000\n");
}else{
printf("%.6lf\n", 1 + log(a / b));
}
}
return 0;
}
/**/