Q = int(input())
for _ in range(Q):
    A,B,C = map(int, input().split())
    if C == 1:
        print(A*B)
        continue

    cnt = 0
    while A > 0:
        if A < C:
            A = 0
            cnt += 1
        else:
            A = min(A//C, A-2*(C-1))
            cnt += 2
    print(B*cnt)