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 ' s salary is 20 % less than b ' s salary , by how much percent is b ' s salary more than a ' s ?
Options: a ) 5 % , b ) 10 % , c ) 15 % , d ) 25 % , e ) none

Answer: d

Question: Problem: how many integerskgreater than 100 and less than 1100 are there such that if the hundreds and the units digits ofkare reversed , the resulting integer is k + 99 ?
Options: a ) 50 , b ) 60 , c ) 70 , d ) 80 , e ) 90

Answer: e

Question: Problem: dacid obtained 45 , 35 , 52 , 47 and 55 marks ( out of 100 ) in english , mathematics , physics , chemistry and biology . what are his average marks ?
Options: a ) 79 , b ) 99 , c ) 47 , d ) 89 , e ) 45

Answer:
c