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: from january 1 , 1991 , to january 1 , 1993 , the number of people enrolled in health maintenance organizations increased by 20 percent . the enrollment on january 1 , 1993 , was 50 million . how many million people , to the nearest million , were enrolled in health maintenance organizations on january 1 , 1991 ? 
Options: a ) 38 , b ) 39 , c ) 40 , d ) 41 , e ) 42

A: e
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Q: Problem: some of 10 % - intensity red paint is replaced with 20 % solution of red paint such that the new paint intensity is 15 % . what fraction of the original paint was replaced ? 
Options: a ) 2 / 5 , b ) 2 / 3 , c ) 1 / 2 , d ) 1 / 3 , e ) 1 / 5

A: c
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Q: Problem: a sum was put at simple interest at a certain rate for 5 years had it been put at 6 % higher rate , it would have fetched 90 more . find the sum . 
Options: a ) 90 , b ) 100 , c ) 200 , d ) 300 , e ) 400

A:
d
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