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: 5 drainage pipes , each draining water from a pool at the same constant rate , together can drain a certain pool in 16 days . how many additional pipes , each draining water at the same constant rate , will be needed to drain the pool in 4 days ? 
Options: a ) 6 , b ) 9 , c ) 10 , d ) 12 , e ) 15

A: e
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Q: Problem: a certain city with a population of 108,000 is to be divided into 11 voting districts , and no district is to have a population that is more than 10 percent greater than the population of any other district what is the minimum possible population that the least populated district could have ? 
Options: a ) a ) 10,700 , b ) b ) 10,800 , c ) c ) 9,000 , d ) d ) 11,000 , e ) e ) 11,100

A: c
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Q: Problem: find the unknown term 8 , x , 62 , - 4 , - 12 
Options: a ) 2 , b ) 4 , c ) 6 , d ) 8 , e ) 9

A:
d
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