In this task, you need to answer the given multiple-choice question on the gain. Gain is the value by which to multiply the input. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: what is 120 % of 13 / 24 of 840 ? 
Options: a ) 436 , b ) 478 , c ) 512 , d ) 546 , e ) 620

A: d
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Q: Problem: 120 students represent x percent of the boys at a school . if the boys at the school make up 30 % of the total school population of x students , what is x ? 
Options: a ) 120 , b ) 150 , c ) 180 , d ) 200 , e ) 250

A: d
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Q: Problem: in a graduate physics course , 70 percent of the students are male and 30 percent of the students are married . if one - sevenths of the male students are married , what fraction of the female students is single ? 
Options: a ) 1 / 3 , b ) 1 / 7 , c ) 1 / 2 , d ) 2 / 3 , e ) 5 / 7

A:
a
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