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: a store ’ s selling price of $ 2240 for a certain computer would yield a profit of 40 percent of the store ’ s cost for the computer . what selling price would yield a profit of 60 percent of the computer ’ s cost ? 
Options: a ) $ 2400 , b ) $ 2464 , c ) $ 2560 , d ) $ 2732 , e ) $ 2800

A: c
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Q: Problem: if a sum of money doubles itself in 5 years at simple interest , the ratepercent per annum is 
Options: a ) 12 , b ) 12.5 , c ) 20 , d ) 13.5 , e ) 14

A:
c
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