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'.

Q: Problem: the average marks of a class of 40 students is 44 and that of another class of 45 students is 70 . find the average marks of all the students ? 
Options: a ) 52.6 , b ) 52.4 , c ) 52.1 , d ) 69.5 , e ) 52.9

A: d
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Q: 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: a
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Q: Problem: 18 times a positive integer is more than its square by 80 , then the positive integer is 
Options: a ) 13 , b ) 10 , c ) 11 , d ) 12 , e ) 14

A:
b
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