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'.

Q: Problem: a large field of 900 hectares is divided into two parts . the difference of the areas of the two parts is one - fifth of the average of the two areas . what is the area of the smaller part in hectares ? 
Options: a ) 435 hectares . , b ) 425 hectares . , c ) 445 hectares . , d ) 415 hectares . , e ) 405 hectares .

A: e
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Q: Problem: for how many integer values of n will the value of the expression 4 n + 7 be an integer greater than 1 and less than 100 ? 
Options: a ) 30 , b ) 28 , c ) 27 , d ) 25 , e ) 26

A: d
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Q: Problem: a salesman ’ s terms were changed from a flat commission of 5 % on all his sales to a fixed salary of rs . 900 plus 2.5 % commission on all sales exceeding rs . 4,000 . if his remuneration as per new scheme was rs . 600 more than that by the previous schema , his sales were worth ? 
Options: a ) 10000 , b ) 12000 , c ) 12019 , d ) 12197 , e ) 12012

A:
a
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