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: if the cost price of 50 articles is equal to the selling price of 20 articles , then the gain or loss percent is ? 
Options: a ) 16 , b ) 127 , c ) 12 , d ) 18 , e ) 150

A: e
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Q: Problem: sarah operated her lemonade stand monday through friday over a two week period and made a total profit of 210 dollars . on hot days she sold cups of lemonade for a price that was 25 percent higher than the regular days . each cup she sold had a total cost of 75 cents and sarah did not incur any other costs . if every day she sold exactly 32 cups and 3 of the days were hot , then what was the price of 1 cup on a hot day ? 
Options: a ) $ 1.50 , b ) $ 1.64 , c ) $ 2.25 , d ) $ 2.50 , e ) $ 3.25

A: b
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Q: Problem: a fruit seller had some oranges . he sells 30 % oranges and still has 420 oranges . how many oranges he had originally ? 
Options: a ) 420 , b ) 600 , c ) 220 , d ) 400 , e ) none of these

A:
b
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