#include<bits/stdc++.h>
using namespace std;

int main()
{
	int t;
	cin>>t;
	while(t--){
	    int n,k;
	    cin>>n>>k;
	    if(n==k){
	        cout<<"0"<<endl;
	    }else 
	    if(n%5==0&&k%5==0){
	        cout<<n/5-k/5<<endl;
	    }else if(n%5!=0&&k%5==0){
	        cout<<n/5-k/5+1<<endl;
	    }else if(n%5==0&&k%5!=0){
	        cout<<n/5-k/5-1<<endl;
	    }
	    else{
	        cout<<n/5-k/5<<endl;
	    }
	}
	return 0;
}