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: uncle bruce is baking chocolate chip cookies . he has 50 ounces of dough ( with no chocolate ) and 40 ounces of chocolate . how much chocolate is left over if he uses all the dough but only wants the cookies to consist of 30 % chocolate ? 
Options: a ) 22.86 , b ) 23.86 , c ) 25 , d ) 26 , e ) 27
a

Problem: if 40 % of a certain number is 160 , then what is 90 % of that number ? 
Options: a ) 270 , b ) 380 , c ) 260 , d ) 360 , e ) 290
d

Problem: a shirt goes on sale for 90 % of its original price . one week later , the sale price is marked down 10 % . the final price is what percent of the original price ? 
Options: a ) 72 % , b ) 81 % , c ) 52 % , d ) 50 % , e ) 28 %

b