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

Q: Problem: a certain university will select 1 of 4 candidates eligible to fill a position in the mathematics department and 2 of 10 candidates eligible to fill 2 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 3 candidates are there to fill the 3 positions ? 
Options: a ) 42 , b ) 70 , c ) 140 , d ) 180 , e ) 315

A: d
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Q: Problem: find the fraction which has the same ratio to 2 / 3 that 3 / 5 has to 6 / 7 
Options: a ) 1 / 5 , b ) 2 / 22 , c ) 3 / 4 , d ) 7 / 15 , e ) 5 / 6

A: d
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Q: Problem: the ratio of three numbers is 3 : 4 : 5 and the sum of their squares is 1250 . the sum of the numbers is : 
Options: a ) 30 , b ) 50 , c ) 60 , d ) 70 , e ) 80

A:
c
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