No one can tell you your chances on hitting that Q47/48/49 because much of it depends on how you were doing before those 10 questions, how many questions you would have gotten right, what level of questions you would have gotten right etc.
The best thing for you would be to improve your timing and finish the test comfortably. In general, leaving questions unanswered carries a larger penalty than answering the questions incorrectly.
It is definitely doable.
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