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 coins are tossed . find the probability of at least 2 tails ? 
Options: a ) 1 / 2 , b ) 2 / 3 , c ) 1 / 4 , d ) 1 / 8 , e ) 3 / 8

Answer: a


Question: Problem: a bag contains 3 blue and 5 white marbles . one by one , marbles are drawn out randomly until only two are left in the bag . what is the probability c that out of the two , one is white and one is blue ? 
Options: a ) 15 / 56 , b ) 41 / 56 , c ) 13 / 28 , d ) 15 / 28 , e ) 5 / 14

Answer: d


Question: Problem: how many different pairs of numbers ( s , t ) such that s = 3 t can be obtained if s and t are selected from the set of number { 0 , 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 } 
Options: a ) 1 , b ) 2 , c ) 3 , d ) 4 , e ) 5

Answer:
e