T = int(input())

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

    if N <= (M // 2) * 4:
        ans = (N // 4) * 3
        print(ans)

    else:
        t1, M = divmod(M, 2)
        N -= t1 * 4
        #print("#",N,M,t1)
        X = N * 2 + M
        t2 = X // 10
        ans = (t1+t2)  * 3
        print(ans)