In this task, you need to provide the correct option for a given problem from the provided options.

Q: Problem: 200 liters of a mixture contains milk and water in the ratio 4 : 1 . if 20 liters of this mixture be replaced by 20 liters of milk , the ratio of milk to water in the new mixture would be ? 
Options: a ) 6 : 1 , b ) 1 : 6 , c ) 2 : 3 , d ) 3 : 2 , e ) 4 : 1

A: a
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Q: Problem: if 25 % of the 880 students at a certain college are enrolled in biology classes , how many students at the college are not enrolled in a biology class ? 
Options: a ) 500 , b ) 600 , c ) 620 , d ) 640 , e ) 660

A: e
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Q: Problem: a bag contains 7 green and 8 white balls . if two balls are drawn simultaneously , the probability that both are of the same colour is 
Options: a ) 7 / 16 , b ) 7 / 12 , c ) 7 / 19 , d ) 7 / 12 , e ) 7 / 15

A:
e
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