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

[Q]: Problem: the ratio of 2 numbers is 3 : 4 and their h . c . f . is 4 . their l . c . m . is ? 
Options: a ) 20 , b ) 24 , c ) 48 , d ) 36 , e ) 60
[A]: c


[Q]: Problem: teas worth rs . 126 per kg and rs . 135 per kg are mixed with a third variety in the ratio 1 : 1 : 2 . if the mixture is worth rs 156 per kg , the price of the third variety per kg will be ? 
Options: a ) rs . 147.50 , b ) rs . 785.50 , c ) rs . 178.50 , d ) rs . 258.50 , e ) none of these
[A]: c


[Q]: Problem: what is the greatest positive integer r such that 3 ^ r is a factor of 9 ^ 10 ? 
Options: a ) r = 5 , b ) r = 9 , c ) r = 10 , d ) r = 20 , e ) 30
[A]:
d