instruction:
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'.
question:
Problem: a total of $ 20,000 was invested in two certificates of deposit at simple annual interest rates of 6 percent and 8 percent , respectively . if the total interest on the two certificates was $ 1,440 at the end of one year , what fractional part of the $ 20.000 was invested at the higher rate ? 
Options: a ) 3 / 8 , b ) 2 / 5 , c ) 1 / 2 , d ) 3 / 5 , e ) 3 / 4
answer:
d


question:
Problem: a sum of money at simple interest amounts to rs . 815 in 3 years and to rs . 865 in 4 years . the sum is : 
Options: a ) s . 665 , b ) s . 690 , c ) s . 698 , d ) s . 700 , e ) s . 720
answer:
a


question:
Problem: tickets to a certain concert sell for $ 20 each . the first 10 people to show up at the ticket booth received a 40 % discount , and the next 20 received a 15 % discount . if 48 people bought tickets to the concert , what was the total revenue from ticket sales ? 
Options: a ) $ 600 , b ) $ 820 , c ) $ 850 , d ) $ 980 , e ) $ 1,140
answer:

b