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'.

Problem: 3 times the first of 3 consecutive odd integers is 3 more than twice the third . the third integer is ? 
Options: a ) 15 , b ) 17 , c ) 19 , d ) 21 , e ) 26
a

Problem: if the charge of staying in a student youth hostel $ 18.00 / day for the first week , and $ 14.00 / day for each additional week , how much does it cost to stay for 23 days ? 
Options: a ) $ 160 , b ) $ 350 , c ) $ 282 , d ) $ 274 , e ) $ 286
b

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

e