Question 1115289
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Given that the sum is 9, we have only 4 possible pairs


    (r3,g6), (r4,g5), (r5,g4), (r6,g3).



It is the full space of events under given restriction.


Of them, only one pair  (r4,g5)  is red 4.


Hence, the conditional probability under the question is  {{{1/4}}}.
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