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'.

Q: Problem: the area of a circle is increased by 1500 % . by what percent has the radius of the circle increased ? 
Options: a ) 100 % , b ) 200 % , c ) 300 % , d ) 600 % , e ) 800 %

A: c
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Q: Problem: in an election between two candidates , one got 60 % of the total valid votes , 30 % of the votes were invalid . if the total number of votes was 9000 , the number of valid votes that the other candidate got , was : 
Options: a ) 2500 , b ) 2520 , c ) 3000 , d ) 3100 , e ) none of these

A: b
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Q: Problem: the price of a t . v . set worth rs . 60000 is to be paid in 20 installments of rs . 1000 each . if the rate of interest be 6 % per annum , and the first installment be paid at the time of purchase , then the value of the last installment covering the interest as well will be ? 
Options: a ) 22678 , b ) 59000 , c ) 26788 , d ) 19000 , e ) 26711

A:
b
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