In this task, you need to provide the correct option for a given problem on probability from the provided options.
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Question: Problem: three unbiased coins are tossed . what is the probability of getting 1 heads and 1 tail ? 
Options: a ) 3 / 4 , b ) 1 / 4 , c ) 3 / 8 , d ) 7 / 8 , e ) 1 / 8

Answer: b


Question: Problem: three 7 faced dice are thrown together . the probability that all the three show the same number on them is ? 
Options: a ) 1 / 38 , b ) 1 / 49 , c ) 1 / 39 , d ) 1 / 42 , e ) 1 / 29

Answer: b


Question: Problem: a certain junior class has 1,000 students and a certain senior class has 800 students . among these students , there are 40 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 ? 
Options: a ) 3 / 40,000 , b ) 1 / 3,600 , c ) 1 / 20,000 , d ) 1 / 60 , e ) 1 / 15

Answer:
c