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 6 ? 
Options: a ) a ) 66 , b ) b ) 77 , c ) c ) 79 , d ) d ) 81 , e ) e ) 82

Answer: a


Question: Problem: how many times digit 5 is used while writing numbers from 100 to 1000 ? 
Options: a ) 648 , b ) 300 , c ) 252 , d ) 225 , e ) 290

Answer: e


Question: Problem: a number when divided by a certain divisor left remainder 241 , when twice the number was divided by the same divisor , the remainder was 102 . find the divisor ? 
Options: a ) 370 , b ) 365 , c ) 380 , d ) 456 , e ) 460

Answer:
c