In this task, you need to answer the given multiple-choice question on the gain. Gain is the value by which to multiply the input. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Problem: on a certain road , 10 % of the motorists exceed the posted speed limit and receive speeding tickets , but 20 % of the motorists who exceed the posted speed limit do not receive speeding tickets . what percent of the motorists on that road exceed the posted speed limit ? 
Options: a ) 10.5 % , b ) 12.5 % , c ) 15 % , d ) 22 % , e ) 30 %
b

Problem: the annual interest rate earned by an investment increased by 8 percent from last year to this year . if the annual interest rate earned by the investment this year was 27 percent , what was the annual interest rate last year ? 
Options: a ) 22 % , b ) 20 % , c ) 25 % , d ) 23 % , e ) 21 %
c

Problem: find the compound interest on rs . 16,000 at 20 % per annum for 9 months , compounded quartely . 
Options: a ) rs . 2522 , b ) rs . 2512 , c ) rs . 2572 , d ) rs . 2592 , e ) none

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
a

