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: what is the average of first 21 multiples of 5 ?
Options: a ) a ) 70 , b ) b ) 77 , c ) c ) 55 , d ) d ) 81 , e ) e ) 82

Answer: c

Question: Problem: what is the next number : 2 , 17 , 257 , __
Options: a ) 2977 , b ) 3837 , c ) 4097 , d ) 4847 , e ) 5387

Answer: c

Question: Problem: a man saves 20 % of his monthly salary . if an account of dearness of things he is to increase his monthly expenses by 20 % , he is only able to save rs . 200 per month . what is his monthly salary ?
Options: a ) rs . 5000 , b ) rs . 25000 , c ) rs . 7500 , d ) rs . 8500 , e ) rs . 9500

Answer:
a