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 man is 20 years older than his son . in two years , his age will be twice the age of his son . the present age of the son is ? 
Options: a ) 11 , b ) 25 , c ) 27 , d ) 18 , e ) 91
d

Problem: 3 / 5 of all married couples have more than one child . 1 / 2 of all married couples have more than 3 children . what fraction of all married couples have 2 or 3 children ? 
Options: a ) 1 / 5 , b ) 1 / 10 , c ) 7 / 20 , d ) 3 / 5 , e ) it can not be determined from the given information .
b

Problem: after 6 games , team b had an average of 75 points per game . if it got only 47 points in game 7 , how many more points does it need to score to get its total above 500 ? 
Options: a ) 5 , b ) 4 , c ) 7 , d ) 3 , e ) 8

d