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: how much percentage 80 is of 480 ? 
Options: a ) 16.5 , b ) 14.33 , c ) 12.5 , d ) 15.8 , e ) 16.66
e

Problem: a certain number of horses and an equal number of men are going somewhere . half of the owners are on their horses ' back while the remaining ones are walking along leading their horses . if the number of legs walking on the ground is 40 , how many horses are there ? 
Options: a ) 8 , b ) 12 , c ) 14 , d ) 16 , e ) 18
a

Problem: the average marks obtained by 100 candidates in an examination is 50 . find how many candidates have passed in the examination , if the average marks of candidates who passed is 70 and that of failed candidates is 20 . 
Options: a ) 33 , b ) 77 , c ) 60 , d ) 29 , e ) 11

c