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'.

[EX Q]: Problem: if the average ( arithmetic mean ) of a and b is 110 , and the average of b and c is 170 , what is the value of a − c ? 
Options: a ) − 120 , b ) − 100 , c ) 100 , d ) 135 , e ) it can not be determined from the information given
[EX A]: a

[EX Q]: Problem: product of two co - prime numbers is 117 . their l . c . m should be 
Options: a ) 222 , b ) 117 , c ) 278 , d ) 767 , e ) 298
[EX A]: b

[EX Q]: Problem: a salesman commission is 5 % on all sales upto $ 10000 and 4 % on all sales exceeding this . he remits $ 31100 to his parent company after deducting his commission . find the total sales ? 
Options: a ) $ 30000 , b ) $ 32500 , c ) $ 35120 , d ) $ 41520 , e ) $ 25460
[EX A]:
b