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'.
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Question: Problem: if a person walks at 14 km / hr instead of 10 km / hr , he would have walked 20 km more . the actual distance traveled by him is :
Options: a ) 50 km , b ) 56 km , c ) 60 km , d ) 70 km , e ) 80 km

Answer: a

Question: Problem: the mean of 50 observations was 36 . it was found later that an observation 48 was wrongly taken as 23 . the corrected new mean is :
Options: a ) 36.5 , b ) 35 , c ) 34 , d ) 33 , e ) 32.5

Answer: a

Question: Problem: ( 35423 + 7164 + 41720 ) - ( 317 x 89 ) = ?
Options: a ) 28213 , b ) 84307 , c ) 50694 , d ) 54094 , e ) none of them

Answer:
d