from math import gcd for _ in range(int(input())): a, b, k = map(int, input().split()) g = gcd(a, b) l = a // g * b le = 1 ri = 10 ** 20 while le + 1 < ri: mi = (le + ri) // 2 if mi - ((mi // a) + (mi // b) - (mi // l)) > k: ri = mi else: le = mi print(le)