instruction:
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'.
question:
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
answer:
e


question:
Problem: find √ ? / 19 = 4 ? 
Options: a ) 76 , b ) 5776 , c ) 304 , d ) 1296 , e ) none
answer:
b


question:
Problem: ages of two persons differ by 22 years . if 6 year ago , the elder one be 3 times as old the younger one , find their present age 
Options: a ) 12,28 , b ) 14,30 , c ) 17,39 , d ) 18,34 , e ) 19,34
answer:

c