import std.algorithm;
import std.array;
import std.ascii;
import std.bigint;
import std.complex;
import std.container;
import std.conv;
import std.functional;
import std.math;
import std.range;
import std.stdio;
import std.string;
import std.typecons;

auto readInts() {
	return array(map!(to!int)(readln().strip().split()));
}
auto readInt() {
	return readInts()[0];
}
auto readLongs() {
	return array(map!(to!long)(readln().strip().split()));
}
auto readLong() {
	return readLongs()[0];
}

void readlnTo(T...)(ref T t) {
    auto s = readln().split();
    assert(s.length == t.length);
    foreach(ref ti; t) {
        ti = s[0].to!(typeof(ti));
        s = s[1..$];
    }
}

const real eps = 1e-10;

alias TA = Tuple!(long, long);

long gcd(long a, long b) {
    if(a < b) {
        swap(a, b);
    }
    if(a % b == 0) {
        return b;
    }
    return gcd(b, a%b);
}

TA minTA(long t, long a) {
    auto g = gcd(t, a);
    return tuple(t/g, a/g);
}

void main(){
    auto N = readInt();
    auto currentVote = tuple(1L,1L);
    foreach(i; iota(N)) {
        auto ta = readLongs();
        auto m = minTA(ta[0], ta[1]);
        auto r = max(currentVote[0]/m[0], currentVote[1]/m[1]);
        auto n = tuple(m[0] * r, m[1] * r);
        while(n[0] < currentVote[0] || n[1] < currentVote[1]) {
            n[0] += m[0];
            n[1] += m[1];
        }
        currentVote = n;
    }
    writeln(currentVote[0] + currentVote[1]);
}

