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

Q: Problem: among 300 students , 56 % study sociology , 44 % study mathematics and 40 % study biology . if 30 % of students study both mathematics and sociology , what is the largest possible number of students who study biology but do not study either mathematics or sociology ? 
Options: a ) 30 , b ) 90 , c ) 120 , d ) 172 , e ) 188

A: b
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Q: Problem: the ratio of three numbers is 1 : 2 : 4 and the sum of their squares is 4725 . the sum of the numbers is ? 
Options: ['a ) a ) 10', 'b ) b ) 12', 'c ) c ) 15', 'd ) d ) 14', 'e ) e ) 9']

A: c
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Q: Problem: the h . c . f . of two numbers is 30 and the other two factors of their l . c . m . are 10 and 15 . the larger of the two numbers is : 
Options: a ) 350 , b ) 250 , c ) 450 , d ) 500 , e ) 620

A:
c
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