.
Under the given condition, there are only three possible outcomes
    (1,1), (2,1) and (1,2).
So, the space of events in this case consists of 3 events with equal probability   of each.
Of them, there is only one favorable outcome (1,1).
Thus the answer to the problem's question is
  of each.
Of them, there is only one favorable outcome (1,1).
Thus the answer to the problem's question is   .
.
Solved.