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