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: solution x is 10 percent alcohol by volume , and solution y is 30 percent alcohol by volume . how many milliliters of solution y must be added to 250 milliliters of solution x to create a solution that is 25 percent alcohol by volume ? 
Options: a ) 250 / 3 , b ) 750 , c ) 400 , d ) 480 , e ) 600
[A]: b


[Q]: Problem: if a ( a - 2 ) = 2 and b ( b - 2 ) = 2 , where a ≠ b , then a + b = 
Options: a ) − 1 , b ) − 2 , c ) 4 , d ) 46 , e ) 48
[A]: a


[Q]: Problem: a survey reveals that the average income of a company ’ s customers is $ 45000 per year . if 50 customers respond to the survey and the average income of the wealthiest 10 of those customers is $ 55000 , what is the average income of the other 40 customers ? is there a way to solve this using weighted average concept instead of doing tedious calculations ? 
Options: a ) $ 27,500 , b ) $ 35,000 , c ) $ 37,500 , d ) $ 42,500 , e ) $ 50,000
[A]:
d