A certain junior class has 1,200 students and a certain senior class has 800 students. Among these students, there are 60 siblings pairs, each consisting of 1 junior and 1 senior. If 1 student is to be selected at random from each class, what is the probability that the 2 students selected at will be a sibling pair?  Choose the correct choice from the following answers: A) 3/40,000 B) 1/3,600 C) 9/2,000 D) 1/60 E) 1/16,000
Total number of ways of choosing one student from each group is = 800 * 1200   Number of cases in which a sibling pair will be got is = 60   Thus the probability that the 2 students selected will be a sibling pair is   = 60 /(800 * 1200)   = 1/16,000   1/16,000
<result>E</result>
A certain junior class has 1,200 students and a certain senior class has 800 students. Among these students, there are 60 siblings pairs, each consisting of 1 junior and 1 senior. If 1 student is to be selected at random from each class, what is the probability that the 2 students selected at will be a sibling pair?