#include <bits/stdc++.h>
using namespace std;
int n,  p = 0,q = 1;
int m;
int main(){

	cin>>n;
	for(int i=1;i<=n;i++){
		int a,b;
		scanf("%d/%d",&a,&b);
		
		int fm = q*b;
		int fz = p*b + q*a;
		int g = __gcd(fm,fz);
		
		p = fz / g;
		q = fm / g;

	}
	if(q==1){
		cout<<p;
		return 0;
	}else{
		cout<<p<<"/"<<q;
		return 0;
	}

	return 0;
}