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: if 1 / 12 of the passengers on a ship are from north america , 1 / 4 are europeans , 2 / 9 are from africa , 1 / 6 are from asia and the remaining 50 people are citizens of other continents , then how many passengers are on board the ship ? 
Options: a ) 120 , b ) 140 , c ) 150 , d ) 160 , e ) 180

A: e
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Q: Problem: how many positive integers less than 100 have a remainder of 6 when divided by 13 ? 
Options: a ) 2 , b ) 7 , c ) 6 , d ) 9 , e ) 10

A: c
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Q: Problem: a certain lab experiments with white and brown mice only . in one experiment , 4 / 9 of the mice are brown . if there are 20 brown mice in the experiment , how many mice in total are in the experiment ? 
Options: a ) 32 , b ) 26 , c ) 36 , d ) 28 , e ) 24

A:
c
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