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

Q: Problem: in a class , 30 students pass in english and 20 students in math , while some students among these pass in both . how many more students do only english as compared to those doing only maths ? 
Options: a ) 10 , b ) 15 , c ) 20 , d ) 25 , e ) indeterminate

A: a
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Q: Problem: among 600 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 ) 180

A: e
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Q: Problem: two numbers are respectively 20 % and 50 % more than a third number . the ratio of the two numbers is : 
Options: a ) 3 : 5 , b ) 4 : 5 , c ) 5 : 5 , d ) 4 : 3 , e ) 2 : 1

A:
b
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