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'.

[EX Q]: Problem: 12.1212 + 17.0005 - 9.1103 = ? 
Options: a ) 20.0015 , b ) 20.0105 , c ) 20.0115 , d ) 20.0114 , e ) none
[EX A]: d

[EX Q]: Problem: for the positive integers x , x + 2 , x + 4 , x + 7 , and x + 17 , the mean is how much greater than the median ? 
Options: a ) 0 , b ) 1 , c ) 2 , d ) 4 , e ) 7
[EX A]: c

[EX Q]: Problem: in a race where 12 cars are running , the chance that car x will win is 1 / 6 , that y will win is 1 / 10 and that z will win is 1 / 8 . assuming that a dead heat is impossible , find the chance that one of them will win . 
Options: a ) 1 / 140 , b ) 1 / 180 , c ) 27 / 410 , d ) 47 / 120 , e ) 57 / 120
[EX A]:
d