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'.

Problem: a , b and c are partners . a receives 2 / 3 of profits , b and c dividing the remainder equally . a ' s income is increased by rs . 400 when the rate to profit rises from 5 to 7 percent . find the capital of c ? 
Options: a ) 3377 , b ) 2899 , c ) 5000 , d ) 2778 , e ) 1991
c

Problem: if x + ( 1 / x ) = 5 , what is the value of w = x ^ 2 + ( 1 / x ) ^ 2 ? 
Options: a ) w = 21 , b ) w = 22 , c ) w = 23 , d ) w = 24 , e ) 27
c

Problem: a number is increased by 50 % and then decreased by 50 % . find the net increase or decrease per cent . 
Options: a ) 25 % , b ) 18 % , c ) 17 % , d ) 13 % , e ) 16 %

a