In this task, you need to provide the correct option for a given problem from the provided options.

Q: Problem: in township k , 1 / 4 of the housing units are equiped with cable tv . if 1 / 10 of the housing units , including 1 / 3 of those that are equiped with cable tv , are equipped with videocassette recorders , what fraction of the housing units have neither cable tv nor videocassette recorders ? 
Options: a ) 23 / 30 , b ) 11 / 15 , c ) 7 / 10 , d ) 1 / 6 , e ) 2 / 15

A: b
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Q: Problem: a certain university will select 1 of 7 candidates eligible to fill a position in the mathematics department and 3 of 10 candidates eligible to fill 3 identical positions in the computer science department . if none of the candidates is eligible for a position in both departments , how many different sets of 4 candidates are there to fill the 4 positions ? 
Options: a ) 420 , b ) 770 , c ) 840 , d ) 165 , e ) 315

A: c
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Q: Problem: a dog takes 5 leaps for every 7 leaps of a hare . if one leap of the dog is equal to 3 leaps of the hare , the ratio of the speed of the dog to that of the hare is : 
Options: a ) 16 : 7 , b ) 15 : 7 , c ) 20 : 7 , d ) 7 : 15 , e ) 14 : 7

A:
b
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