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'.
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Question: 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

Answer: c


Question: Problem: find the simple interest on rs . 520 for 7 months at 8 paisa per month ? 
Options: a ) 277 , b ) 270 , c ) 291 , d ) 266 , e ) 121

Answer: c


Question: Problem: at what rate percent per annum will the simple interest on a sum of money be 7 / 5 of the amount in 10 years ? 
Options: a ) 4 % , b ) 7 % , c ) 9 % , d ) 3 % , e ) 14 %

Answer:
e