T = int(input())

Z = 0

def ZhaLan(N,M):
    S1 = N // 4 
    S2 = M // 2
    if S1 == S2:
        Z = S1 * 3
        return Z
    elif S1 < S2:
        Z = S1 * 3
        return Z
    else:
        while N >= 4:
            M = M - 2
            N = N - 4
            Z = Z + 3
        if N >= 4 and M < 2:
            N = N - 4
            M = M + 2
        return Z
   


for _ in range(T):
    N, M = map(int, input().split())

    if M == 0:
        Z = N // 10 * 6 

    elif N == 0:
        Z = 0
    elif N == 0 and M == 0:
        Z = 0
    elif N > 0 and M > 0:
        Z = ZhaLan(N,M)
    print(Z)