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

Q: Problem: jo ' s collection contains us , indian and british stamps . if the ratio of us to indian stamps is 4 to 2 and the ratio of indian to british stamps is 5 to 1 , what is the ratio of us to british stamps ? 
Options: a ) 5 : 1 , b ) 10 : 5 , c ) 15 : 2 , d ) 20 : 2 , e ) 25 : 2

A: d
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Q: Problem: if m = 3 ^ n , what is the greatest value of n for which m is a factor of 19 ! 
Options: a ) 8 , b ) 10 , c ) 12 , d ) 14 , e ) 16

A: a
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Q: Problem: two vessels having volumes in the ratio 3 : 5 are filled with water and milk solutions . the ratio of milk and water in the two vessels are 2 : 3 and 3 : 1 respectively . if the contents of both the vessel are empties into a larger vessel , find the ratio of milk and water in the larger vessel . 
Options: a ) 99 : 61 , b ) 99 : 160 , c ) 61 : 160 , d ) 61 : 99 , e ) 99 : 160

A:
a
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