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

Q: Problem: if the ratio of two number is 5 : 7 and lcm of the number is 320 then what is the number . 
Options: a ) 15 , b ) 9 , c ) 10 , d ) 11 , e ) 35

A: b
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Q: Problem: a certain high school has 500 students . of these students , 40 are taking music , 20 are taking art , and 10 are taking both music and art . how many students are taking neither music nor art ? 
Options: a ) 430 , b ) 440 , c ) 450 , d ) 460 , e ) 470

A: c
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Q: Problem: the compound ratio of 5 : 7 , 3 : 2 and 4 : 5 ? 
Options: a ) 1 : 7 , b ) 6 : 5 , c ) 6 : 7 , d ) 4 : 7 , e ) 6 : 9

A:
c
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