In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: a certain lab experiments with white and brown mice only . in one experiment , 2 / 3 of the mice are white . if there are 11 brown mice in the experiment , how many mice in total are in the experiment ? 
Options: a ) 39 , b ) 33 , c ) 26 , d ) 21 , e ) 10

A: b
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Q: Problem: if ( x + 3 ) ^ 2 / ( 2 x + 15 ) = 3 , then the difference between the two possible values of x is : 
Options: a ) 8 , b ) 10 , c ) 12 , d ) 14 , e ) 16

A: c
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Q: Problem: the average age of 15 students of a class is 15 years . out of these , the average age of 3 students is 14 years and that of the other 11 students is 16 years . the age of the 15 th student is 
Options: a ) 9 years , b ) 11 years , c ) 14 years , d ) 7 years , e ) 25 years

A:
d
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