In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.
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Question: Problem: a , b and c started a business with a total investment of rs . 90000 . a invests rs . 6000 more than b and b invests rs . 3000 less than c . if the total profit at the end of a year is rs . 8640 , find b ' s share . 
Options: a ) rs . 2592 , b ) rs . 2520 , c ) rs . 2880 , d ) rs . 3360 , e ) none of these

Answer: a


Question: Problem: a man is 24 years older than his son . in six years , his age will be twice the age of his son . the present age of the son is 
Options: a ) 14 years , b ) 28 years , c ) 20 years , d ) 22 years , e ) none

Answer: e


Question: Problem: if 42.24 = k ( 14 + m / 50 ) , where k and m are positive integers and m < 50 , then what is the value of k + m ? 
Options: a ) 6 , b ) 7 , c ) 8 , d ) 9 , e ) 10

Answer:
b