Concept:Total possible selections are equally likely. Count the ordered pairs whose sum is a prime number.Explanation:P={1,2,3} and Q={2,3,5}Total possible selections =3×3=9List the favourable pairs:(1,2) gives 3, which is prime(2,3) gives 5, which is prime(2,5) gives 7, which is prime(3,2) gives 5, which is primeSo the favourable outcomes are 4.Probability =total outcomesfavourable outcomes=94Answer:94