n = int(input()) av_vel = [] for a in range(0,n): vel1 ,vel2 = input().split() vel1 = int(vel1) vel2 = int(vel2) spatium = vel1 time = spatium/vel1 + spatium/vel2 av_vel.append(spatium*2/time) for b in range(0,n): print(int(av_vel[b]))# your code goes here