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

Problem: 8 men and 2 boys working together can do 4 times as much work as a man and a boy . working capacity of man and boy is in the ratio
Options: a ) 1 : 2 , b ) 1 : 3 , c ) 2 : 1 , d ) 2 : 3 , e ) none of these
a

Problem: in a class of 87 students 41 are taking french , 22 are taking german . of the students taking french or german , 9 are taking both courses . how many students are not enrolled in either course ?
Options: a ) 6 , b ) 15 , c ) 24 , d ) 33 , e ) 54
d

Problem: a jar contains a mixture of ab in the ratio 3 : 2 . when 20 l of mixture is replaced with liquid b , ratio becomes 2 : 3 . how many liters of liquid a was present in mixture initially .
Options: a ) 12 , b ) 15 , c ) 16 , d ) 20 , e ) 36
e